I own a 1995 3.4L Camaro with 185 Km and am having some problem which nobody can figure out. The computer shows no codes and engine light stays off. Basically, the car seems to hold back once in a while, and doesn't accelerate, when I try to accelerate and does this for about 10 to 15 seconds...and while it does this it also makes a popping noise under the car a couple of times and then accelerates...I've changed the spark plugs and wires back to ac delco and put a new fuel filter. My mechanic suggested fuel pump or fuel injectors, but I think if it was one of those then the engine light would come on and it wouldn't be intermittent. Please help.

 

could be your converter check your fuel pressure

run some injector cleaner and see if that helps at all

does your exaust smell funny at all? if it does thats a sign of a clogged converter

 

If/when you had your last emissions test, how did your #s look?

 

I believe my Nox was 300ppm or around there and other numbers were zero. I also just went under the car and banged on the cat and it rattles inside. This means the cat needs to be replaced??

 

that means the catalyst inside is broken, and is not burning the unburned hydracarbons from the engine. Could also be restricting flow.