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GTR engine problem

dairyboy

By dairyboy,
in Engines & Forced Induction

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dairyboy Collaborator

dairyboy

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Another problem just come to mind - been reading the ECu resetting threads and it seems like my ECU should be reset already. My car battery doesn't hold any charge whatsoever and is usually left there for 2 or more days. Do I still need to short certain wires of the wiring loom just to turn it into diagnostic mode then let it reset itself that way?

blind_elk Grand Master

blind_elk

Posted
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when the car is turned on why would the battery affect anything? as the alternator is supplying enough voltage for everything so how could the ecu 'sense poor voltage'??
Not only is the alternator supplying volts to run everything, it is supplying volts to recharge the battery. And with a dead battery, it is supplying HEAPS of volts to try and recharge the battery. The ECU can sense this, and reckons its not a good thing.

A new battery could well solve the problem. And changing the battery will effectively cause a ECU reset.

bangin Enthusiast

bangin

Posted
Posted
Ok...

Parts needed - plugs, battery and possiby O2 sensor and inlet gasket

Need to look at - plugs, inlet gasket and O2 sensor

Anything else to that list? Troubleshooting this mofo makes me pull all my hair out

just reading other peoples responses and they are all possible solutions so heres mine. check afm you said it had a z32 unit and now the stock units. check afm connection. the stock afm's may be faulty and if the stock ecu senses this it runs in limp mode and that maybe your reasons for hard to start and bad idling. i think when the ecu senses the fault in the afm it will not allow the motor to rev very high. just a thought. good luck

Whoneedstherapy Veteran

Whoneedstherapy

Posted
Posted

Just a quick thought here.

Was it running a standard ecu with the z32's when you got it?? IF so when you changed the AFM's to standard im guessing you didn't have the computer remapped to suit the standard afm's??

This could be one part of your problem now as if you had a standard ecu with z32 afm's your ecu has definately been remapped, which isn't really a bad thing, but in changing to a standard air flow meter the ecu is going to be getting incorrect signals from the standard airflow meter.

IF i was you i'd take it to a good workshop, sit down and talk to them about it, put all the gear it came out with back on and see how you go.

blind_elk Grand Master

blind_elk

Posted
Posted
Ok...

Parts needed - plugs, battery and possiby O2 sensor and inlet gasket

Need to look at - plugs, inlet gasket and O2 sensor

Anything else to that list? Troubleshooting this mofo makes me pull all my hair out

A BLOODY BATTERY!!!!!!!!!!! :D

Rowdyr32 Mentor

Rowdyr32

Posted
Posted

Try pulling the plugs off each injector one at a time whilest the engines running. Could possibly give you an indication if its an injector. Also could it be the valve clearances? Have you done a compression check on the engine yet? Have you checked the fault codes on the ecu? The 26 I just put in my car ran like a pig and idled rough because I wired up the knock sensors around the wrong way. Good luck man!

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