97 v6 3.8L Camaro. Automatic. Here's the problem:

I made a thread a few months ago about a problem I was having going up hills and sometimes on flat ground. The car would slightly jerk like it was losing power. Well, it quit and ran great until a few days ago. The other night I was driving home and noticed the car would pull itself without me even pressing the gas pedal. It only did it twice and stopped. I didn't think nothing of it and figured the gas pedal was sticking. Well, the next day I stopped and filled my car up with gas, and as I was pulling out the car made a hard jerk and I heard a "tinging" noise under the hood, so I drove it home and the whole way there it would jerk constantly, and lose power up hills. Nothing like before. It will do it worse when I take off from a stop.

I was told it's water in my gas. I put gas treatment in it, and drove it a lot hoping it would finally go away if it was water, and it's still doing it. Hasn't improved yet. If it is water in the gas, how long will it take for it to go away? Until the tank is empty? Cause I was told the gas treatment would make it go away.

So, the noise under the hood hasn't gone away. I searched for the noise, and noticed it's coming from inside the air hose. (the hose that is attached to the air filter box.) It's a rattle sound like something is broke or lose.

I was also told it could be my catalytic converter clogged. I searched online to see how to test it, and I stuck my hand against both exhaust tips and there was a steady flow of air coming out of both, so if it was clogged it would have been weak. So, I'm not leaning towards that anymore unless it's still possible?

Any other ideas of what it could be? It runs fine when I get it up to 50+mph the jerking stops, but once I'm at a slow steady speed, or taking off from a stand point, it jerks so bad that it makes stuff inside the car rattle and vibrate. Like it's wanting to shut off, or misfiring.

 

Also, the noise from under the hood isn't constant. It happens every now and then, rarely. Mainly at idle for a few seconds and it goes away.

 

Could this also be a sign of a vacuum leak? If so, how would I test to see if that's the problem?

 

any check codes? IAC maybe?

 

No codes.

 

And when I rev it, it won't go past 4000rpm. It kind of like bottoms out, and sounds weird.

It seems to shift fine and smooth.

 

And some more information. I have no problems starting it. It doesn't shut off while idling, but it idles rough, like every 5-10 seconds it "shakes" like it's losing power.

it jerks while going in reverse also. Jerks in over drive and drive.

 

Ok then, did you pull the intake "hose" off and look to see if anything in there looks strange? Is something loose inside and rattling around? When you open the throttle by hand, does the throttle blade on the TB feel tight?

 

Test you throttle position sensor and your maf. When did you last change your spark plugs, wires and coil packs?