So first off, if this has been asked a million times before sorry, go ahead and delete this and I'll go back to searching.

Anyways I have a 91 GTA with the L98, with around 91,000 miles on it. I bought it not too long ago. When I drove the car prior to buying it, it ran hard and would go WOT no problem. However, 30 minutes after that I was driving it home and the car lost all power and began to backfire. The car would bog down and wouldn't get up above 30 MPH regardless of throttle position, but would suddenly surge randomly.

Since that time I have changed the spark plugs and wires (crappy 7mm), adjusted the timing, put a new water pump on, flushed the coolant, and checked for vacuum leaks.

I've been reading and reading and I'm thinking maybe my fuel filter or O2 sensors might be screwed up? any ideas would be great, if I don't get it running soon I'm cutting my losses. Thanks.

 

check your fuel pressure. check your timing make sure the dis. is tight and hasn't moved when you where driving it. any check engine light?

 

The SES light came on for a minute but went away and hasn't come back since.

 

if it was the o2 then the light should be on all the time the car is in closed loop.

 

Well, that rules out that theory. I am going to have to do some looking at the fuel system as that is what I keep hearing about.

 

yeah check that fuel pressure and the dis. before spending any money.

 

Could it be the ECM going bad? I checked my TPS and it looked fine, but that's not a very good way to see if it's still in working order.

I got it up to 4000 RPM while in park at a gradual pace, but if I step on it hard the RPM's drop way down and it almost dies. Any and all ideas are appreciated because this is causing me to pull out my hair.

 

Check the code that SES set. It'll still be stored in the ECM.

 

Check for lowfuel pressure/low volume or an exhaust restriction (cat convertor)