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Hi everyone,

Iv'e only had my Z a week or so and am trying to get it running properly..

At the moment it is running in safety boost,i know this as i connected a voltmeter to the wastegate solenoids and the ecu cuts the supply to them on full throttle leaving me with 5-6 psi..

I checked the water temp sensor circuit and replaced the sensor so thats ok..

When i came to look at the det. sensor i noticed i didn't even have one and the wiring harness connector had a resistor wedged in there instead..

I understand that this was probably done to override the sensor..

I tested the resistance of the resistor and it was about half a megohm or 500,000 ohms..

I then did a live volt check from the det.sensor circuit to the ecu and it was 1.95 volts and the manual says it should be about 2.5 volts..

Does anyone know if that is the correct resistor rating and if 1.95 volts i'm getting at the moment is ok..I just want to get it running ok before i replace det. sensor properly..

p.s funny thing is the guy i bought it off has a receipt from S.E nissan for a new det sensor fitted 3 years ago???

Featured Replies

Correct value is 1MOhm ;)

 

Done an ECU code check?

  • Author

yes it comes up code 55 all ok..

Just thinking a 1 megohm resistor is double the resistance ive got in there now so it will give me lower than 1.95 volts ive got at the moment..

Maybe something wrong with wiring then..

thanks...steve

if theres a code 55 then you must not have a fault with the det sensor, or it would have logged a code.

 

perhaps the det sensor was replaced but the short loom to it wasnt, a deffinate false ecconnomy!

 

maybe the half meg resistor+a loose/bad connection was enough to simulate a det signal voltage and not a fault (OC/SC) code

  • Author

Yes cheers good point...

Does anybody know of any other reason that the ecu will run in safety boost when its showing no fault codes,signal from temp sensor ok and its not detonating and car runs well otherwise...

Thanks....steve

Take the car out for a drive, and get it into positive boost, then test for ECU codes without switching the ignition off.

 

code34 (det sensor) often does'nt occur until the car is taken into boost.

  • Author

Thanks...Iv'e just re-connected the resistor properly took car out and it's finally out of safety boost with 12v at solenoids all the time..hooray!!

Trouble is the boost has only gone up to 7 psi.

Anyone got any ideas...boost leak!...weak wastegate actuator!...

Cheers for your help...steve

Thanks...Iv'e just re-connected the resistor properly took car out and it's finally out of safety boost with 12v at solenoids all the time..hooray!!

Trouble is the boost has only gone up to 7 psi.

Anyone got any ideas...boost leak!...weak wastegate actuator!...

Cheers for your help...steve

 

It may be a leak somewhere,try all pipes from balance bar area,hard pipes,knackerd recircs/pipes,if you have aftermarket gauge sometimes the small pipe to rear can get bent over especialy if you have routed it through bulk head etc,just take time out to try check all known vac lines/pipes,but could allso be stock gauge if you using that only, giving crap reading(mine was at +14 even in saftey)

 

 

Tony :)

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