Engine wont rev above 5000 rpm

[leper421]

My 91 5spd has had a problem with going above 5000rpm for a while now. What happens is the engine starts shaking, and the rpms will fluctuate between 4800-5200. This happens in neutral and in all the gears (havent gotting that fast in 5th, though). If I let the car get that high while driving, the engine puts out little to no power.

I've done a full tune-up recently, so I know its not caused by any of those items. My guess is either the fuel pump cant supply enough fuel, or that the fuel pressure regulator is crapping out. I dont have a fuel pressure gauge yet, so I cant check to see if I'm right.

[jkeyser14]

Have you tried replacing the fuel filter... A dirty fuel filter can cause all kinds of weird problems, including what you described.

[KarmaPolice]

This happened to my nissan truck I had. I believe the computer does this so you can get it to a mechanic and thats it. Try the maf that could be the problem. I found out too late for my truck but hey now I got a 240. Good luck.

[technoman]

I would try cleaning all the electric conectors on the engine. take a look at your mass air flow meter.

[95_240sx]

The same thing happened to my 95 SE, It turned out to be bad gas. Get yourself some good premium gasoline and put some fuel injector cleaner in there. Should help.

Rick

[technoman]

You should allways use high octane.

[leper421]

I fixed the problem. It turned out to be a bad 5th gear switch on the transmission. The ECU thought I was always in 5th and the rev limiter was kicking in.