I have a noise at about 2500 rpm in gear not valve chatter. It sounds like exhaust on right front right under passenger side feet. Also in neutral(6speed) if I rev it lightly it sounds like a powerstroke diesel at first but then gets to a normal sound. Any thoughts. Banged on heat shields no noise got under it with a flashlight no cracks but I can't see the manifold.

 

Common issues on these motors: 1) exhaust manifold leak. 2) loose heat shields. 3) pinging, or spark knock. You need to explain and pinpoint the sound a little better. Does it do it when motor is cold and hot, under load etc.

 

Thanks. OK, it happens when its warm, when Its under a load in 2,3,4th gear at about 2500rpm. Sounds like valve chatter but from under the glove box area, or where passengers feet go. The diesel sound is when its not under a load in my driveway and warm just on the initial tap of the gas it goes away after the rpms go up. Its hard to explain other than it sounds like a powerstroke.

 

What kind of gas are you using? Try running some high octane and see if it stops. It sounds like pinging to me by what you are saying. If the higher octane gas helps, let me know and I can give you some steps to help stop the issue.

 

I never use 87 I only use 89 and it does sound like an octane ping. Should I go up to a higher octane than 89?

 

I appreciate your knowledge and help thank you.

 

Mine does the exact samething

 

I had the same thing happen with auto tranny my crossover pipe was hitting my tranny skid.

 

Is it possible that the tapping noise you hear on and just off idle are the fuel injectors? They do make a clicking noise as a cycle.

 

No its not that. Thanks though.