Frequently Asked Questions

Q: Brake Lights Stay On

I have an annoying problem: I changed my master cylinder due to a leak. The operation was a complete success, with no extra parts left over! When I drive the car, and then stop, my brake lights are on. I’ll tap them, they go out and stay out. What’s up?

A: Two possibilities. There is a return spring on the peddal and if it came off for some reason while you were replacing the master cylinder (or maybe it wasn’t on from before) then you are relying on the internal springs of the master cylinder to push your pedal all the way back and not quite making it.

The other possiblility is that you just have to adjust the switch a little bit forward. It’s on the peddal assembly under the dash.

A: It’s probably the plunger switch down under your dash.

A: Have you checked your brake light switch on the pedal assembly? There is a switch under the dash that turns the lights on until the brake pedal come up high enough to contact the switch and interrupt the circuit. You will either need to adjust the switch down a bit to insure contact with the brake pedal, or you may need to move the brake pushrod to a higher hole on the brake pedal if the pedal isn’t coming up far enough to touch the switch.

My guess is that since you can get the brake lights to go off by taping the pedal, it will require only a small adjustment of the switch to make things right.

A: Are you talking about the brake lights on the back of the car or the brake warning light on the dash? Others have addressed the brake lights on the back so I won’t go there. If it’s the brake warning light then the problem is in you splitter valve below the master cylinder. Most likely, it air in the line causing it to go out of balance. If this is the case, you must bleed the brakes again to remove all air from the lines.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Rear Tail Light Problem

I am having a lot of problems with my tail lights. All the problems started after one of my bulbs burnt out and I tried to replace them. Any ideas?

A: I guess I better go back to lightbulb school, or get glasses. I did not realize that the wrong bulb in the wrong socket would make the light do so many weird things. But as always, thanks to your suggestions, I solved it half way through ripping th dash apart.

A: Let me guess, you found an 1156 single where an 1157 double filament should have been?

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: “GEN” Dash Light On

What could the problem be when my dash “GEN” light stays on all the time? In the last 2 weeks on a 1968 350 2bbl, I replaced the alternator with a Delco remanufactured unit and then the regulator went so I replaced it. Last week, only a day after the regulator was replaced, the “GEN” idiot ight began to blink on and off randomly. I let the car cool and check the connections to the alternator, the regulator, and the plug through the firewall that connects to the fuse box I believe. The “GEN” light stopped flashing but is on very dull.

I took the alternator off and had it tested last night. It tests okay. I am not familiar with any test procedures for a regulator. I did buy a new one though and will try and put it in tonight. One odd thing I noticed last night. When I start the car, the “GEN” light comes on dull. HOWEVER, when I turn the ignition on, but don’t turn it all the way to start the car, none of the idiot lights come on any more. It used to be that if you turned the key left or right so it just opens the circuit for the battery to run (i.e. to listen to the radio), the TEMP, GEN and another light came on. I haven’t checked the fuse yet to see if the fuse for the dash lights is still good. But if the fuse were blown, why would the “GEN” light be on, as dull as it is. ANY CLUES???

A: It’s possible that you have a faulty ground in your dash cluster and this is causing a “ground loop” through the GEN light. You can make a temporary ground with a clip lead (a test lead) or just a piece of wire and see if that cures the problem.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Backup Lights on a 1968

I have a 1968 Firebird, 6 cylinder with 3 speed standard shift on the steering column. I’m trying to figure out how to adjust when the back up lights come on. I can’t find the sensor. Any ideas where it is?

A: From the 1968 Pontiac Service Manual, pg 12-22:

Back Up Lamp Switch

….(T)o adjust back up lamp switch use the following procedures and Fig. 12-27. (For auto, see neutralizer switch adjustment instructions).

All Manual Transmission with COLUMN Shift

1. Insert 0.090 gauge pin thru hole in switch body, and into hole in Drive tang.

2. Set transmission gearshift lever in reverse position.

3. Insert switch drive tang in shifter tube slot with tang touching R.H. edge of slot and assemble switch.

4. Remove gauge pin.

All Manual Transmission with FLOOR Shift

1. Place lever in reverse position.

2. Position switch so that plunger is fully depressed against lever.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Ballast Resistor

Does anybody know what the voltage going in and out of the ballast resister should be? I know I asked before but is a resistor wire going into the ballast resistor normal? Also our new resistor seems to get quite warm…is this normal when new? or always? The wiring going in and out seems fine. Also is anybody using an Accel supercoil? You know the big kinda boxy yellow one…does it have internal resistance? If so does that alter the requirement for an external ballast resistor or resistor wire?

Here are my particulars…My Accel Supercoil has 1 ohm resistance so I’m assuming it has no internal resistance. With my ballast resistor in place and connected i have like 9.6 volts going in and only like 4.6 going out to the coil. But if I disconnect the ballast resistor I have 12.3 volts coming from the resistor wire. If I connect the resistor wire (coming from the ignition switch) to the ballast resistor but dont connect the wire from the ballast resister to the coil + I have 12.3 volts at BOTH sides of the ballast resistor. Then when I hook the wire from the resistor to the coil my voltage drops back to like 9.6 going in to the resistor and 4.6 coming out and the resistor gets quite hot. The ballast resistor itself has 1 ohm resistance across the terminals with nothing connected. Also the ballast resistor gets so hot that it actually smokes but the wiring seems fine on both ends

A: You should NOT have BOTH a resistance wire AND a ballast resistor. I think our Firebirds (at least in 1969) used a resistance wire. If you have a coil with internal resistance, then you should NOT use an external resistor or resistance wire. If you want to know if you coil has an internal ballast resistor, measure the resistance across the coil. It should be 1.0-1.5 ohms if there is NOT an internal ballast resistance and about 4 ohms if there is.

Information about your configuration (ballast wire/resistor/internal coil) and what the voltages should be at different places:

First, you will always get battery voltage (12.3 in your case) at the end of the wire going to the coil when it is NOT connected. You could put a 1k resistor on the end and you’d still get battery voltage. This is because currect is not flowing and the Potential of 12.3 Volts is still there.

Next, I’m assuming that when you took your voltage reading that you grounded the “-” side of the coil or made sure that the points were in contact, with the ignition in the “on” position but the car not running. If so, then your reading indicate that your resistor wire is about 0.6 ohms. That is just about what it should be. That being the case, I’m not sure why you have a separate ballast resistor at all. Does it look factory, like it aught to be there? If not, ditch it. Your 0.6 ohm resistor wire and 1 ohm coil will give you about 7.5 Volts to the coil (static) which is fine.

As a side note, during cranking you should have full battery voltage to the coil to provide a “hotter” spark. This is accomplished either by a wire to the coil from the starter OR a separate wire from the ignition switch “start” terminal.

DON’T STOP READING.

Having said everything above, I just read the ACCEL catalog. It says:

“NOTE: ACCEL 140001 Super Coils are supplied with a 0.85 ohm Ballast Resistor which must be used in conjunction with the vehicles original ballast resistor, if equipped”

I think I remember you said you had a super coil. If you do and you’re using their ballast resistor, I’d call ACCEL and find out why it gets so hot and smokes. That or go back to a standard coil.

A: GM didn’t use ballast resistors, they used resistance wire to the coil. The voltage at the coil should be about 9 volts. The yellow accel supercoils used an extra ballast resistor to lower that to 6 volts. Sounds like someone did a little creative wiring. Maybe they replaced the resistance wire to install a GM HEI distributor, then changed their mind and rather than find resistance wire, used a ballast resistor, plus the one for the super coil.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Brake Lights Stay On

I have an annoying problem: I changed my master cylinder due to a leak. The operation was a complete success, with no extra parts left over! When I drive the car, and then stop, my brake lights are on. I’ll tap them, they go out and stay out. What’s up?

A: Two possibilities. There is a return spring on the peddal and if it came off for some reason while you were replacing the master cylinder (or maybe it wasn’t on from before) then you are relying on the internal springs of the master cylinder to push your pedal all the way back and not quite making it.

The other possiblility is that you just have to adjust the switch a little bit forward. It’s on the peddal assembly under the dash.

A: It’s probably the plunger switch down under your dash.

A: Have you checked your brake light switch on the pedal assembly? There is a switch under the dash that turns the lights on until the brake pedal come up high enough to contact the switch and interrupt the circuit. You will either need to adjust the switch down a bit to insure contact with the brake pedal, or you may need to move the brake pushrod to a higher hole on the brake pedal if the pedal isn’t coming up far enough to touch the switch.

My guess is that since you can get the brake lights to go off by taping the pedal, it will require only a small adjustment of the switch to make things right.

A: Are you talking about the brake lights on the back of the car or the brake warning light on the dash? Others have addressed the brake lights on the back so I won’t go there. If it’s the brake warning light then the problem is in you splitter valve below the master cylinder. Most likely, it air in the line causing it to go out of balance. If this is the case, you must bleed the brakes again to remove all air from the lines.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q:
Dash Printed Circuit Board

Does anyone know where I can get shematics for the Dash Printed Circuit Board for a 1969 ?

A: You can order a wiring diagram from Classic Industries, or from most of the other resto catalogs. They run about $7.00 and are about 20 pages in length.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Engine Compartment Wiring Diagram for 1968

I’m in the middle of installing a new engine wiring harness. Would you Mine is attatched to the rear of the exhaust manifold on the passenger side. I feel this is not correct because the new wiring harness does not reach it in that position. The wiring harness that I’m replacing looks as if it was homemade so I can not use it as a referrence.

A: I found a schematic in the 1968 Pontiac Service Manual.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Fuel and Temperature Gauge Problems

I have an inoperative fuel gauge ( always full ) and temperature gauge ( always cold ); the oil pressure and alt gauges are both operational. Several “shadetree mechanics” tell me the problem may be in an improperly grounded rally cluster metal case. I recall that the wiring harness plug has a green wire that is attached to the metal case with a sheetmetal screw. I thought that was a ground wire. However one fellow was talking about grounding the unit/case by way on the metal strip that is behind the high-beem indicator light in some way ??? I’m lost !!! What advice can be offered. I’ve removed the gauges several times before and may have not gotten a solid ground.

A: There are actually multiple “grounds” on the rally cluster. When I get home tonight, I pull the wiring diagrams and check out where the fuel gauge and temp gauges derive their grounds. Is it possible that the problem is not in the rally cluster itself, but in the fuel and temperature sending units themselves? Do you have an ohm meter that you can use to check the inputs from these sending units?

I know from experience that disconnecting the wire at the sending unit in the gas tank will cause the fuel guage to read full. There is also a ground wire on the fuel guage sending unit which tends to get rusty and break off after a few years. If this happens, you will see the same problem – fuel guage reading full.

Concerning the temperature guage, one simple test of the temp guage is to hook up an ohm meter to the temp sending unit located on the intake manifold when the car is cold. Take take a reading. Then start the car and allow it to come up to operating temp. The value on the meter, (the measure of resistance in the sending unit) should change as the engine warms up. If it doesn’t move, you have a bad sending unit, or the wrong sending unit. I’ve seen a case where someone installed a temp sending unit that was designed for the “idiot light cluster” instead of the rally gauge cluster. The temp sending unit for the idiot cluster is a switch, the temp sending unit for the rally cluster is esentially a variable resister based on temp. If the readings change, then it is a safe assumption you have a rally guage sending unit and it is operating normally. The next step would be to then check if you get the same reading at the plug which goes into the back of the rally guage cluster. The temp wire is the green wire going into pin 2 of the connector.

Did your car come stock with a rally guage cluster? If not, the problem may lay in the fact the the “pin-out” for the rally guage cluster is different than the pin-out for the idiot light cluster. I can provide the pin-out for the connector if you need it. (Note: See ‘Replace an original Dash cluster’ for more information)

A: I pulled the wiring diagrams on the rally guage cluster and wiring harnesses last night. Before I get into the gory details, I’m not sure how familiar you are with basic electrical circuits so here is what you need to understand about them before you can understand and diagnose your problem.

The electrical circuit(s) in the car are 12 volt, DC. That means, that every circuit must have a complete connection from the positive side of the battery to the negative side of the battery. The negative side of the circuit is usually refered to as “ground” and in most cars, (your firebird included), the negative side of the battery is connected to the frame/chasis of the car esentially making every metal part of the car the negative side of the battery.

Now, in reference to your gauge problem:

The first thing to keep in mind is that your problem is probably NOT being caused by ANY missing “ground”s on the guage cluster itself. Why? Two reasons. 1) The ground connections on the rally guage cluster are ONLY used for the instrument lighting, turn signal indicators, and high beam indicator circuits. 2) The “ground”s for the gauge circuits, (oil preasure, temp, and fuel guage), are at the “sending units”, (the ammeter is a completely different type of circuit and totally independent). However, I say “probably not” because I don’t have the specifics on the internals of the gauges themsleves so I can’t say if the gauges use any “reference ground” source.

The way the cluster and gauge circuits are designed is that the fuel gauge, oil pressure gauge, temperature guage, and brake indicator light, ALL share the same +12V feed, which comes into the cluster on pin 10 of the connector via two PINK wires. Since the oil pressure gauge is working, then you have the +12V into the cluster on these pink wires AND any possible “refernce ground” source for the gauges is probably there as well.

Since you have +12V to the gauges, that means that one of four problems exist for the fuel gauge and the temperature guages. (They will have to be diagnosed seperately since the problem with the fuel gauge circuit might not be the same as the problem with the temp gauge circuit.) The possible causes for the malfunctioning gauges are: 1) a break in the wire from the gauge to the sending unit, 2) a bad sending unit, 3) a bad ground at the sending unit, or 4) the gauge itself is bad.

To diagnose the fuel gauge, here is what I would do. Locate where the rear wiring harness, (the one from the tail lights) meets the main harness. (Starting in the trunk, follow the wiring harness from the tail lights up to the where the rear harness connects to the main harness. There will be a seven wire connector at this point. Disconect the two harnesses. (The TAN wire is fuel gauge circuit). Working with the connector coming from the FRONT of the car, take a piece of wire and make a connection from the TAN wire in that connector to a GOOD ground, (a clean metal part on the body.) Now sit in the driver’s seat and turn the key to the on position. No need to start the car.) IF the gauge and the TAN wire from the gauge are good, the fuel gauge should immediately drop to EMPTY. (Don’t leave the key turned on for more than 5 – 10 seconds). If the gauge doesn’t drop to EMPTY, then the problem is either the gauge itself, or the tan wire from the guage cluster connector to the connetor you currently have your grounding wire attached. If the fuel gauge drops to EMPTY, then you are bummin’ because you will have to drop the tank to get at the fuel sending unit. There is either a break in the TAN wire in the rear harness, a broken ground wire on the sending unit, (the most likely source of the problem), or a bad sending unit itself.

The temperature guage is a little easier to test. The temp sending unit is located on the intake manifold on the top left front right near the thermostat housing. Disconnect the wire from the sending unit and run a length of wire from that connector to a nice clean ground on the engine. The sending unit wire should be dark green by the way. Once again, sit in the driver’s seat and turn the key to the on position. The temp guage should immediately jump to HOT side of the gauge. If it does, you have a bad sending unit. If it doesn’t, then either the dark green wire from the sending unit to the gauge cluster is broken or the temperature guage itself is broken.

Keep this in mind, the idea is to complete a circuit from the positive side of the battery to the negative side of the battery by going through the gauge in cluster AND the sending unit. Any break in the circuit along the way and the gauge quits working. The positive side of the ciruit is at the gauge cluster and the negactive side of the circuit is at the sending units.

I hope this helps. Good luck in your diagnosis

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Gauge Conversion for 1967-1968

I’m getting ready to convert from idiot lights to a gauge cluster on my 1968 conv. I’ve been to the FAQs and there’s a lot of good related stuff, but I do not see a wiring diagram for the gauges. Did I miss it?

A: Chip as you can see theres lots of discusion on gauge conversions. 1967 and 8 pose a big problem in that the pinout is different on the dash connector. However regardless of what you hear,its not as simple as changing a few pins around. Sure you can get the oil and water to read, but to get the ammeter to work you will have to rework the harnesses all the way to the voltage regulator. This will mean a new forward lamp harness as well as a dash harness. There are extra wires in the rally gauge setup that the idiot light ones dont have. You could redo the lamp harness and add wiring to the bulkhead connector , change the pinout and add wiring to the dash harness. OR buy the correct harness(s). Any way you go its not as easy as changing speedo /dash assembly. 69s are a different story… bout time they wised up.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: How do I hook up my reverse lights

I have a question regarding my car’s backup lights… I have a coulumn shift automatic, and I am unsure which switch is connected to the backup lights. All I know is that they do not work. My neutral safety switch does work though. If anyone has a diagram, or some pictures of where this switch is, please send them to me. Thanks

A: They are both in the same switch housing, the purple wires are the neutral safety, the thinner wires (I forget the colors) are the back-up connection. Check power in and out, wiggle the shifter while you do that. Jump the connector to see if the BU lights actually work!

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Identifying the Correct Dash Cluster

I am at a loss as to what is the proper gauge cluster for my bird. The build sheet for my car calls for a clock (which is nonexsisteant) and gauges. I have a console and an automatic TH400, what could be the configuration. The build sheet is for my car, I checked the numbers.There is a large hole in the front of the console, I am guessing that this was for the clock. any information would be greatly appreciated.

A: The only “hole” should be some what oblong with two mounting holes, a large hole indicates butchering by previous owner. The rally guages are available at major parts shows [67/68 differ] not cheap! The wire harness would show additional connectors designating that car had ralleys. The under dash 3 guage was available at that time, but is even more rare.

A: The optional clock was mounted on the console, ahead of the shifter. If you’ve got a hole, that’s it. I’d start looking around for one! They aren’t too hard to find, but they can be pricey if you want one that actually works. You might try checking out Hemmings, or the Ames Performance website. Good luck!

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Loose Ground

I have a 1969 coupe, that has a pecuiliar problem. Whenever the headlights are on, the turn indicators & hi beam indicator are dimly lit. When the turn signals are engaged,(either direction) they all blink. Furthermore, the gas guage indicator drops as soon as the lights are engaged. If you turn the rheostat on the headlight switch all the way down (where you can’t see the lights), the gas reads normally, and the the turn signal indicators work properly. I have replaced the headlight switch and the dimmer switch. I have not been able to locate a wiring diagram of the car, particularly the instrument panel, short of searching for an original service manual, (and shelling out the big bucks for one.) If anyone has dealt with this type of problem, or happens to have the wiring diagrams, I would greatly appreciate it.

A: I had the very same problem on my 69. It turned out to be bad dash ground. The dash gauges/lights are grounded through a thin metal strip that is sandwiched between the radio and the dash. If the radio has been removed or changed or if the connection is not tight, your dash lights/gauges will go nuts. I corrected mine by adding a ground jumper from the back of the gauge cluster to the metal dash at a convenient location.

A: The turn signal indicators and gas gauge are likely source by the same circuit that sources the cluster lamps. When the dash lamps are at the brightest intensity, most of the current is diverted toward the shorted lamp and starving the turn indicator (flasher which requires significant current to operate) and gas gauge. This is why the turn signals stop working. Moving the rheostat to the dim the cluster lamps removes the short and current is available to turn indicators/gas gauge causing them to work correctly.

A guess is that there is a low resistance shorted lamp on the cluster assembly. The short should identify itself by excessive heat. Feel around the back of the cluster for a spot that appears warmer then the rest. If you don’t find it, remove cluster lamps (instrument illumination only) one at time until all have been checked. If all the lamps are removed and the problem seems to remedy as each lamp is removed, there is a low resistance short in the main feed to the rheostat. If all the lamps are removed and the problem persists, there is short between the rheostat and the circuit card on the back of the cluster.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Power Window Problem

Okay Guys, I need your help. Yesterday, the power windows on my 1968 Convt quit. I tried looking for a fuse in the fuse block that handles the power windows. None there specific to power windows. On 12-41 of the 1968 Service manual (the tan one, not maroomn one) it shows a circuit breaker tied in with the horn circuit. Where is this circuit breaker?? is it the fuse?? cuz the fuse for the horn appears good. Help!!! It’s damn hot in a convertible with the windows up

A: There is a Circuit Breaker under the Driver’s side Cowl-Trim Panel (kick panel). There is also a Junction Block on the Firewall near the Fuseblock and one on the engine side of the Radiator Support (passenger side). One of these is for a conv. so try checking that first. If all looks ok, you might have to replace the motor unit.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Rear Tail Light Problem

I am having a lot of problems with my tail lights. All the problems started after one of my bulbs burnt out and I tried to replace them. Any ideas?

A: I guess I better go back to lightbulb school, or get glasses. I did not realize that the wrong bulb in the wrong socket would make the light do so many weird things. But as always, thanks to your suggestions, I solved it half way through ripping th dash apart.

A: Let me guess, you found an 1156 single where an 1157 double filament should have been?

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Replace an Original Dash Cluster

Does anyone know if it is possible to replace an original Dash cluster with telltale lamps with a Ralley Gauge cluster without big changes in the wiring of the dash. I hope somebody has some info on this.

A: Information can be found in the Interior F.A.Q.s – Dash: https://FirstGenFirebird.org/f-a-q/interior/dash/

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Starter Wire

Does the purple 12 ga wire from the wiring harness to the starter go to the “R” terminal or the “S” terminal on the starter? and what is the other terminal for?

A: The 12 gauge purple wire goes from the starter switch, through the firewall plug harness, then down to the “S” terminal of the starter. The “S” terminal serves to actuate the starter SOLENOID windings. When the solenoid pulls the starter drive to engage the starter, it also closes a couple contacts via a disc on the solenoid assembly. This energizes the starter motor windings and turns the starter. The other contact that is made with this disc is the “R” terminal (Relay). This terminal supplies a “direct” path to the ignition coil positive terminal while the starter is energized. The reason for this dedicated path is to maximize coil current while the starter is “taxing” the system, i.e., creating a voltage drop. When the engine starts and the starter switch is released, the “R” terminal is disconnected. The ignition coil then continues to be energized via the ignition switch loop and the resistance wire. I have diagrams if you need them.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Wire/Solenoid Problem

After driving my 1968 on the highway when I pull into my neighborhood, the car starts to cut out a little. If I stop the car, many times it won’t start until it cools down, and when it does start, it runs very poorly, cuts out and dies. I started looking at the set up and the selenoid is very close to my headers. Also, the wire running to the selenoid is potentially touching the pipes. I plan on redoing the wire, but what else could it be. Is the selenoid just getting too hot and how about the poor running?

A: The wire and solenoid running too close to the exhaust will cause starting problems. However, after starting it should not affect the running characteristics of the motor unless you’ve burned through the wire insulation and it’s shorting out. I would check the positive battery very carefully. Also, check the negative cable and make sure it is making a solid connection to the motor. Also check the gas line and make sure it is not too close to the exhaust. You could be boiling the fuel and creating vapor lock.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q:
Dash Printed Circuit Board

Does anyone know where I can get shematics for the Dash Printed Circuit Board for a 1969 ?

A: You can order a wiring diagram from Classic Industries, or from most of the other resto catalogs. They run about $7.00 and are about 20 pages in length.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Gauge Conversion for 1967-1968

I’m getting ready to convert from idiot lights to a gauge cluster on my 1968 conv. I’ve been to the FAQs and there’s a lot of good related stuff, but I do not see a wiring diagram for the gauges. Did I miss it?

A: Chip as you can see theres lots of discusion on gauge conversions. 1967 and 8 pose a big problem in that the pinout is different on the dash connector. However regardless of what you hear,its not as simple as changing a few pins around. Sure you can get the oil and water to read, but to get the ammeter to work you will have to rework the harnesses all the way to the voltage regulator. This will mean a new forward lamp harness as well as a dash harness. There are extra wires in the rally gauge setup that the idiot light ones dont have. You could redo the lamp harness and add wiring to the bulkhead connector , change the pinout and add wiring to the dash harness. OR buy the correct harness(s). Any way you go its not as easy as changing speedo /dash assembly. 69s are a different story… bout time they wised up.

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Identifying the Correct Dash Cluster

I am at a loss as to what is the proper gauge cluster for my bird. The build sheet for my car calls for a clock (which is nonexsisteant) and gauges. I have a console and an automatic TH400, what could be the configuration. The build sheet is for my car, I checked the numbers.There is a large hole in the front of the console, I am guessing that this was for the clock. any information would be greatly appreciated.

A: The only “hole” should be some what oblong with two mounting holes, a large hole indicates butchering by previous owner. The rally guages are available at major parts shows [67/68 differ] not cheap! The wire harness would show additional connectors designating that car had ralleys. The under dash 3 guage was available at that time, but is even more rare.

A: The optional clock was mounted on the console, ahead of the shifter. If you’ve got a hole, that’s it. I’d start looking around for one! They aren’t too hard to find, but they can be pricey if you want one that actually works. You might try checking out Hemmings, or the Ames Performance website. Good luck!

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.

Q: Replace an Original Dash Cluster

Does anyone know if it is possible to replace an original Dash cluster with telltale lamps with a Ralley Gauge cluster without big changes in the wiring of the dash. I hope somebody has some info on this.

A: Information can be found in the Interior F.A.Q.s – Dash: https://FirstGenFirebird.org/f-a-q/interior/dash/

Any proposed updates, changes, pictures, and/or corrections, please use our comment section below (may need to click on permalink to access comments feature). Information is subject to change and offered as is without any warranties or guarantees. Please review our Term's Of Use for more information.