Ok somtimes when I'm driving my car at a steady rpm it will go wacky the rpm gauge that is plus i do fill it in the engine. At first I thought this might be the fuel filter or somthing to do with the fuel system, fuel pump or MAF. The RPM guage will bounce a little up and down. I just replaced the fuel filter so next i guess I will clean the injecters and replace the fuel pump or MAF. Any help would be great.

Oh yah its a 92 z28 5.0 TPI stock

 

I took it to the only mechanic out here and they ran a test on it and it came up clean. Everyone suggests fuel filter but I already replaced it.

 

Well, you don't have a MAF, so you can rule that out

Does the SES light come on?

Have you checked for codes?

Given it a tuneup lately? (cap/rotor/plugs)

 

Well I just got new plugs and fuel filter I might have mistaken the MAF with ECM. I really dont know how to get codes but It might be electrical after reading some other threads about similiar problems.

 

theres an article in the Tech articles on the homepage of
thirdgen.org

that tells u the codes and how to get them.. that is, if the SES light is on..

did u put the fuel filter on correctly? if u put it on backwards fuel wont flow properly.

Did the mechanic test the fuel pressure? the injectors may be dirty as well..

some other things to ponder upon..

 

I had the same type of problem and after beating my head on the
dash a couple times I found that the rubber hose from the fuel pump to the metal line inside the tank had a hole in it. The only reason that I found that is because I was changing the fuel pump thinking that was the problem. After that the car is runnig great.

 

I can second all that.