valvetrain noise under load
03-07-2009, 10:38 AM
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valvetrain noise under load Alright guys and gals, looking for a little help here, I'm gettin bad valvetrain noise. Driving around town at 30mph, sounds like it should, nice and quiet(valvetrain that is 
). I get this valvetrain noise when the car is under high load low acceleration configurations. For example, when i go up a big hill it will make the noise. It also makes the noise under hard acceleration. I have adjusted the valves twice to double check my work, and it still makes the noise. Pre-load is at 3/4 turn past zero lash (used to be 1/2 turn but figured I would tighten it a 1/4 turn more just in case that was too loose but it still makes the noise). Rather than just start taking stuff apart, I would like a second opinion. Thanks Folks.
). I get this valvetrain noise when the car is under high load low acceleration configurations. For example, when i go up a big hill it will make the noise. It also makes the noise under hard acceleration. I have adjusted the valves twice to double check my work, and it still makes the noise. Pre-load is at 3/4 turn past zero lash (used to be 1/2 turn but figured I would tighten it a 1/4 turn more just in case that was too loose but it still makes the noise). Rather than just start taking stuff apart, I would like a second opinion. Thanks Folks. 
03-07-2009, 04:29 PM
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Sounds more like an exhaust leak to me. Check around all your exhaust ports, around the spark plug boots, header bolts and flanges to see if there's any carbon buildup.
At first start up put your hand around all these areas to see if you can feel anything as well. Exhaust leaks can sounds exactly like excessive valvetrain noise. Check for loose spark plugs as well.
At first start up put your hand around all these areas to see if you can feel anything as well. Exhaust leaks can sounds exactly like excessive valvetrain noise. Check for loose spark plugs as well.
03-07-2009, 04:44 PM
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I remember once my daughter filled up my tank and she put medium grade and when I drove it hard to get on the freeway i heard the valves so maybe its the gas?
03-07-2009, 08:29 PM
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Well among further investigation, it appears to be a "lean misfire". It just recently started doing this, but stumbles a little bit as well at higher loads as well as the detonation, or "valvetrain" type noise that I had described earlier. Thanks for the heads up, Im going to take a look at fuel pressure tomorrow as well as filter to see if I'm lacking pressure then look for any possible air leaks that would cause it to run too lean. I'll keep you guys updated.
