Dakotawagner

Hello all, first post on this site, i hope i am posting in the right section.
So i have had a reoccurring issue with my 2003 350z:
car goes into limp mode, or at least something that seems like limp mode. The car revs up very slowly only allowing it to reach roughly 30 mph. I have gotten the following codes:

P2127- throttle/pedal position sensor/switch “E” circuit low
P2138- throttle/pedal position sensor/switch “D/E” circuit low
Naturally i replaced the accelerator position sensor, also performed the ECU hard reset, and relearning process.
Problem still occurs intermittently, throwing the code and limp mode. Once i turn the car off and reset the code the problem goes away for a while, maybe a day.
Today i got the code
P0605- internal control module read only memory (ROM) Error.
The car would not accelerate whatsoever. I pulled over and turned the car off, reset the code and the car started up and drove home fine. I’m assuming i need a new ECU or ECM, however I’m not sure and i’d Love some suggestions for troubleshooting. Thanks

dkmura

iTrader: (64)

Welcome- this not a common issue with Z33s. I'd take the Z into a local Nissan dealer and have an experienced tech with a Consult III perform a thorough diagnostic. Most dealerships charge an hour of shop time, but this varies by shop.

Dakotawagner

So I took my car to nissan. Told them what I had done, which included replacing the sensor, resetting the ecu, and performing the APS relearn. Two hours later I received a call to come pick up my car. I get there, and the tech tells me that they fixed the issue by resetting the ECU and preforming the relearn process. I told him this wouldnt work, but he assured me that it would. I said "okay thanks! I'll see you tomorrow when the car goes back into limp mode.
Long story short, after multiple attempts to explain to them what the issue was, the tech finally agreed to go through my wiring harness and test my ECU. What they found was that when the timing chains were done on my 350z by the previous owner they had painted the cover which all of the wiring harness grounded into. By removing the paint around where the grounds were, the circuit was able to be completed without interruption. Odd issue that I'm sure no one else will ever experience, but if they do I hope they find this forum.

dkmura

iTrader: (64)

Thanks for posting what happened, as this shows the value of having an experienced tech examine the issues. Good on you for insisting they stay on the case until a solution was found. There was NO WAY any of us behind a keyboard could have figured this one out...