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Vct Problem With Z32, Pfc And Standard Ecu

Ryanrb25

By Ryanrb25,
in Engines & Forced Induction

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Ryanrb25 Grand Master

Ryanrb25

Posted
Posted

hey guys, im aware that the vct shares either an earth or power with other sensors like the o2 sensor etc but my VCT isn't clicking and on the hand controller the vct switch doesn't come on and the extm stays on 5.00v and the 02-1 stays on either 0.04v or 0.00v...I had recently installed a Z32, pfc which im pretty sure isn't the cause of the problem because i unplug the afm and wack the standard ecu back in and still nothing. I have added power to the vct solinoid to see if that was the cause but it clicks fine. I can find 12v on the plug however. Car is getting TUNED tuesday next week and i want it to be sweet!

any ideas people?

paulr33 Grand Master

paulr33

Posted
Posted

put the car in gear and clutch pedal in, tap the accel, VCT should turn on

VCT wont engage with the car in neutral

for VCT to engage on the std ECU or the PFC the following must be true;

RPM must be less than 4500rpm (default, adustable on PFC)

NTR must not be active (must not be in neutral)

TPS must be more than 0.0 (which is really around 0.33v ish) - ie; open the throttle a bit

RPMGTR Community Regular

RPMGTR

Posted
Posted
so if the vct is working when in neutral i take it there is a problem so where else in the system??

i will have to do some more investigating on my 25 then.

Usually just the neutral switch in the gearbox not connected/working.....the ECU thinks the car is 'in gear' so VCT is enabled

SATO GTS Community Regular

SATO GTS

Posted
Posted

well after checking my neutral switch and the way my car behaves i realised that the neutral switch is playing up and causing my vct to operate when in neutral . fc hand controller came in handy to tell me if the switch was working and only in some positions was it registering .. now have to find out why is does not work. i quess that having done 200'000 kms plus its well and truly worn out.

  • 2 months later...
Bennett Mentor

Bennett

Posted
Posted

Hey guys i have the same problem in that my vct isnt coming on. I reved the car in both neutral and in gear with clutch in and still no clicking noise. My power fc says its not even sending the signal to turn on the vct and so the vct receives no voltage and i have tested this to make sure with a multimeter.

Do u think that my neutral switch could be stuffed the other way, making the car think im always in neutral and so no vct? Also wheres the neutral switch both on the car and on the power fc so i can check?

paulr33 Grand Master

paulr33

Posted
Posted

how are you testing this theory?

drive around in 2nd gear, under 4500rpm and accel a bit

watch ETC, SENSOR SW CHECK

does "VCT" have a black dot next to it?

if so, the PFC is turning the relay on

if VCT doesn't come on - ie: solenoid is shagged etc, the PFC wont know this

as in, as far as the PFC knows, the relay is ON once it has black dot

if the oil line was say unplugged, the PFC wouldnt know this

Bennett Mentor

Bennett

Posted
Posted

Thats exactly wat i looked at. there was no black dot next to it. But i just tried it again then and now its working for some reason so very strange but its the first time i have ever heard the car turn the vct on (havent had the power fc long and havent driven it with the new ecu yet). So i put the stock ecu back in and the vct stopped working again. I could tell because the switch was getting no voltage and also the click didnt appear. Why do u think the stock ecu doesnt want to turn the vct on? But the power fc will?

Bennett Mentor

Bennett

Posted
Posted

And also i cant drive the car cos front pannels are missing to fix them and i have no licence. I did also notice that when the vct started working - at the same time my idle became really rough and now hesitates and is rough when i accelerate. Why would this be?

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