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Just a quick one for the brains trust, Having troubleswith the CTS on an RB25 might by a faulty sensor or Hot starts were not dealt with whilst car got tuned remains to be seen (however unpluging the sensor and the car starts first cank every time hot or cold) so im going to replace the sensor anyway just to rule it out, My question is the motor is an RB25 however the ECU is a Z32 NIStune soooo which sensor??? or are they all the same??

cheers

Andrew

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The more I think about it, it seems more logical that a sensor be paired with an ECU rather than a motor.??? But I'm a nuts and bolts kinda guy and hate wiring and electrical. So I could be totally off but the reason for this line of thinking is I do not know if all sensors pickup temperature at a linear rate in relation to another.. Ie; is 3v on an rb25 sensor the same temp as 3v on a z32 sensor?? I think I need some sort of ECU diag software via consult ??

I use ECUTalk (http://ecutalk.com/ecutalk.aspx), it's free and will show you what the ECU sees as the coolant temp. but you will need a consult cable though.

Quick Q have you ever tried unplugging the sensor and seeing what the ECU defaults to? I've heard 0, 40 and 80 degrees ? just trying to get my head around why it goes from not starting at all to strating 1st crank like a brand new car. Or does having this unplugged trigger some closed loop map??? so much to learn, I hate not understanding shit..

Iv got an RB25 with Z32 (type 2) nistune in it.

Ill try it this on the weekend n check it on nistune n consult n let you know what it does.

That would be awesome should hopefully give a pretty definitive result.

I thought the coolant temp sensors were all the same in the Jap cars from that era?

Give me a Z32 Vin and I'll check them in Nissan Fast

Through a bit of searcing on here i gather 20/26 are the same but cant find much on 25, Kinda fits to as my 20 CTS is Yellow and my 25 one is brown/reddish.

Edit; I had a look on interwebs for a random z32 VIN couldnt find one,

Ok do I'm waiting for my consult cable to arrive, do I thought I would clean the AAC valve in the mean time this lead me to discover that the factory T piece that goes into the AAC was deformed and barely "seated" for want of a better word, I'm sure this would have caused a vacuum leak although vacuum at idle was a. Healthy 17 to 18.. Sooooo is this just a coincidence or could this affect warm start??? ( time to find out if Nissan sell the T piece on its own or am I going to be raped and have to buy An AAC valve whole)

  • 1 month later...

Well not much has changed, busy time of year and track only car = neglect.

So Nissan only sell the AAC whole as the T is pressed into it they wanted 650 or some such. So called SSS for second handy for 50 bux cleaned it up and replaced it so AAC clean and no vacuum leaks. Got consult cable and demo version of conzult with some limited functionality. The Cts seems to be working as the temp goes up idle for 15 20 mins and it went upto about 80 degrees C no faults logged either except for fuel temp sensor ( I didn't even know it had one of those)??

So still at a bit of a stale mate?? Spoke to unigroup (who tuned it) and he reckons it could be the z32 ECU running the 25 that might be spazzing out..??? He's booked out till mid jan so if I figure it out by then great, if not he can cause I'm over it..

  • 1 year later...
  • 2 weeks later...

Yeah not sure about that, he said he had to set some pretty unusual values, possibly for warm crank on sartup it's been a long time

Fair enough, nistune is always having new features added, so possibly wasn't available when yours was tuned. Either way whatever he did worked!

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