I forgot to mention the noise was more on the driver's side than the passenger's side. Where should I start? I thought maybe a bad spring, but they are dual springs & they all passed visual inspection. If a spring failed it would keep the valve open too long right? That might account for the slight backfire through the intake. If a pushrod was bent it would not open the valve up enough, would that make it backfire through the intake? If a lifter collapsed it would not open the valve enough or at the right time right? I'm not sure where to start looking from here.
