Tach problem - need help

[Specvengeance]

Here's my problem. I've got a 91 240sx, KA24DE. My tach isn't working and the car won't rev past appx 3000 rpms. Could it be the cam angle position sensor? ECU? My SAFCII isn't reading RPMs either, its not just the tach on the car. I have a wideband 02 hooked up and at idle the a/f is around 10, and when it stops revving its around 20.

Any and all help appreciated. Thanks in advance!

[PDavis40]

sounds like a bad maf or something to do with the maf.. Does it sound like a rev limiter when you try to rev it?

[Specvengeance]

I replaced the maf and I am having the same problem.

But you are defiantly right it just feels like it is hitting a limiter or like it's in limp mode.