My 93 Z28 was running rough and would not rev over 1500 rpms. It would start to bog and lose rpms. It would idle smooth and does not smoke. I figured it was the opti and just finished changing it. I also added a new water pump. The car runs the same now as it did before. Any ideas what is wrong? It seems like it is not getting enough fuel. Has this happened to anyone else? If you think you might know what's is wrong please post.
Thanks for the help.

 

I had the same experience on my 85 Firebird. on it, it turned out to be the computer itself. I know it wasn't an LT1 but just a suggestion.

 

MAF, maybe? I'm no expert but a similar thing happend to me when my MAF wasn't totally pluged in (on my IROC), maybe it's bad. Just a guess. Hope it helps


Daniel

 

sounds to me like the MAP sensor on top of the intake manifold.....

 

Hi guys, I forgot to post that I tried changing the chip to a Hypertech alone and then piggyback on the stock chip. I also changed the fuel filter. I think it may be the TPS or cat is clogged.
Anyone other ideas? Thanks

 

I though a bad TPS would make it idle erratically Just curious though.

 

Today I changed the TPS and MAP sensor. Still runs the same. Tommorrow I may drop the y-pipe and see if the cat was clogged.
Any other ideas? Thanks

 

whats the fuel pressure at?

check 02 sensor readings while engine is bogging.

 

pull your fuel filter down and blow through it. see if its clogged. a bad filter will make the car run like ***.

 

when this happened to me, my cat was clogged

 

same here, clogged cat, but it got progresivley worse. did you sense something was amiss leading upto this?

 

Well since its a 93 the MAF is outta the question, I had a similar problem in my 86 Berlinetta (2.8L) turned out the fuel pump was bad, I would definaltly check the fuel pressure, im not sure what the pressure is supposed to be off the top of my head...but im sure someone here does.


Fullagar

 

It was the cat. After I gutted it the car ran good. I am putting on another cat I have that has low miles. Thank you to all that responded.