The car has been doing this since I got it and I've yet to figure it out. Basically if I go above 4,800rpm I hear a low-toned popping sound coming from somewhere in the front of the car. It will pop repeatedly until I let off the gas or shift into a higher gear. I feel a drop off in power as well.

Other than that the car runs awesome. Idles fine, drives great until I hit those high rpms. Any ideas on what it could be?

 

TTT

 

you may be blowing out spark up top and detronating, or it couold be pinging. I dont know what popping you could be talking about.

 

What do you mean by blowing out spark? What would it be detonating?

 

Where is the popping coming from? out the exhaust or up front? I about died when I seen the title (pooping)

 

I did write 'pooping' didn't I?

Anyways, it's definietly coming from the front of the car. I would say somewhere in front of the tranny.

A buddy of mine rode in my car last night and I had him listen to the noise. He said it sounded like it was backfiring. I applied probably 1/2 throttle all the way up to ~4,700rpm. He wanted to hear it again so I reved her up to ~redline but at 1/3 throttle or so. This time it didn't make the sound.

He suggested my cat could be clogged up causing the car to backfire. Does this sound right?

 

Thats possible, but usually when the cat is clogged its slow to rev and down on power. I know you dont want to hear what seems to be the generic answer but Optispark is one culpret maybe as well as a bent pushrod or something not allowing normal valve actuation (or valve timing). Fuel or lack thereof could make the trouble as well.

 

The thing that's throwing me is it will only make the sound when under load. So I get the feeling it's something having to do with the torque twisting or knocking parts together somewhere in the front end.

The second time I got on it last night with my buddy in the car it wouldn't do it because there wasn't that snap of torque. Then again it does it at the top of fourth gear when I'm WOT.

She runs fine all througout the rpm range unless I really hammer it so I don't think anything's bend in the valvetrain. Otherwise I'd hear it just reving the car.

I just don't understand the loss of power. Only when it's under moderate load will it make this sound and then drop off in power.