OK, once again I need HELP!!! I read my computer and I have no code that says it's the MAF however, i did test it and it works geat as per the test. So I decided to purchase another Computer and it reads the same, No problem except code 31 which I have the Air disconected (85 300zx 2+2), The car starts great but I can not get it pass 2000 RPM.

Question? Could it be a vacum hose? or what can be disconnected to get by pass the problem so I can have a better idea were to start. The car is in great condition, totally redone, but does me no good tojust have it parked.

SHold I take it to Nissan and bend over, or can a mechanic resolve the issue.
Like I said I have the Manual and all seems well. PLEASE HELP!!!!!!!!!!

 

I'm still going to have to say it's MAF related. Either there isn't a good connection, or your wiring is FUBAR

 

I have to agree with ZBum it's like was said. I've had this problem in the past even though it wasn't throwing an error code. See if you can get ahold of a new or at least known working MAF. Do you know anyone else who owns a Z31? If so maybe you could borrow their MAF just to see if it works.

 

I will try another although I have two and acrding to the manual they both test good. I will also tone out the wire to the ECU. see if all is ok. this is driving me ZZZZZZZZZZZZZZZZZ

 

Just because the AFM is testing good doesn't mean the entire circuit is good. Test everything from the AFM to the ECU.

 

I'm starting to think its the Iddle control, I will test for continuity and then replace with another one I have. I will keep everyone inform.

 

get an ohm meter and a wiring diagram and test for no break/ shorts there.

 

resolved RPM issue,it seems that I found in the harness a bridged wire from the iddle control that was cut at the ECU. and went on back to the rear passenger pannel... A box by the spare tire. anyways this wa done and I have no reasson why the old owner did it. as soon as I cut the bridge going to tha back the car iddled back to normal. I connectect it and once agin could not get pass 2000 rpm.
Anyways, the ECU should not have had that wire bridged. So everything is fine now. Thanks everyone for your suggestion

 

UPDATE: RPM issue resolved, wire harness had an TP side open to the ECU. fixed
Thanks everyone.

 

I am having the same problem,i do not see a wire bridged by my spare.

 

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