1990 300zx dont have any idea

[stewart_soldier]

When I crank my 300zx it idles like a champ, but when you give it gas the RPM will rise to 2500 no more then back down to 1000. Back and forth back and forth. I have no clue the only suggestion that Ive gotten so far was the EGR valve may be stuck.

[beavis327]

First you need to see if there is any codes stored in ecm. If not make sure you didn't swallow any water through the air intake. 300's are known for bad air flow meter and main culprit is moisture with cold air filters. Car sounds like it is stuck in fail safe and usually will set a code. Yes 300's sometimes had a carbon build up issue inside egr tubes but would need to see egr temp to confirm. CAr also known for injectors but you said car idles fine so that you can scratch off the list.

Hope this helps

[Q45tech]

Study your FSM [ecu section] and see the things that cause limp mode and limit rpm to 2500 rpm]

[stewart_soldier]

Is there a site I can get on that could kind of explain the ecu and what Im looking for. Im still learning mechanic work. I still dont know alot especially when it comes to imports. How do I see if it is limp and adjust it to 2500 rpm.

[Q45tech]

Failure of external signals [from sensors] to ecu will cause it to run in limp mode, limiting rpm. So that it is kinda drivable to get to expert technican for service.

A year or two in Votech school will do wonders in explaining automotive technology, as will a few text books.

http://www.amazon.com/Automoti...48311h ... c...65667/

[stewart_soldier]

I know electronics and wiring on the apache helicopter but auto is another ballgame thanks for the help. is there any sites you know of that i can get engine diagrams and wiring schematics for these cars.