I have a 1994 lumina z34 3.4 DOHC 148k
I recently purchased this vehical,but came across a problem.
the car had backfired wile driving and every since then when i start the vehical if cold it runs fine! Now as soon as it warms up, i cant accelerate without it choking out and stalling. i can get it up to speed slowly but any harder on the accelerater it will choke out! starts right up again fine. also at a idle it will stall. i pulled the codes, and the code reader came up with 32 codes anywheres from a map sensor to a crankshaft positioning sensor but mostly have to do with the emissions and the list goes on! i cant seem to find the problem. also to mention the catalytic convertor does echo alot when driving not sure if thats plugged or not but please i have very little money and not so sure about these engines!

Not to scare you, but I seem to remember reading (some years ago) that the sending unit for the oil pressure
would suck oil up the wire like a wick.

If the oil made it all the way back to the computer, it would fry the computer.

I would locate a service manual for the car and find the oil pressure sending unit and see if the wire is coated
in oil.

You can't see it from the outside, but you may be able to pull back some of the wire's sheathing, you need to
look at the actual strands of wire to see if they're coated in oil.

If not, then you have other issues like possibly a bad ground.

Scott

It actualy fired back thru the plenium & throttle body?

The backfire may have caused " soft" codes to set in the putr that once cleared may cure problem. Try pulling the ECM fuse leave out for at least 30(per GM repair manual) minutes then reinstall.

i'll try that! its worth a shot. although i brought it to a mechanic and he replaced the Crankshaft positioning sensor. said come get it and then i drove down the road and same thing happend?? its a on going process here, what else can i do?