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i narrowed down my coolant temp sensor being an issue for my cold morning start ( low idle on startup unles i touch the throttle pedal then it picks up and its all normal)

have found genuine sensor for s14 nothing r33 specific unless i pay $$$ from nissan. so would s14 be same?

part number seems same as r33?

if anyone can run it in fast or knows it would be great

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i narrowed down my coolant temp sensor being an issue for my cold morning start ( low idle on startup unles i touch the throttle pedal then it picks up and its all normal)

have found genuine sensor for s14 nothing r33 specific unless i pay $$ from nissan. so would s14 be same?

part number seems same as r33?

if anyone can run it in fast or knows it would be great

Sure it's not your AAC valve? (Not to be confused with IAC)

yes that is the one , i did all the testing and it come down to sensor.

i seen online s14 one looks identical so if you know part number to s14 and r33 one so i can see if they match

only thing is my old one is red , but that wont matter

  • 2 weeks later...

tested it this morning and its better but not 100%

when its been left overnight and car fully cools off the revs are low on startup then i touch acc pedal they go up to 1.5k until its warmed up they drop down and runs fine after that

every hot start is perfectly fine and idles great

anything else to look at?

  • 1 month later...

anyone with some pointers on removing the cold start valve, it was hard enough locating it, let alone removing it, do i have to take off the inlet manifold? i have been having a cold start issue ever since i found water in one of my spark plug holes, i dryed it out, changed plugs, then next day when trying to kick it over it starts then will die if i do not apply throttle, revs upto 2000rpm then drops down back to normal as car warms up, tryed reseting the ecu with paperclip, work fine though its telling me no errors, while car was running on 5 cylinders it would start fine but run like shit, now it starts like shit but runs fine, after quite a few hours researching i narrowed it down to faulty coilpack, coolant temp sensor or cold start valve, what do u guys think??? btw where is the coolant temp sensor?

Edited by hypo33

i narrowed down my coolant temp sensor being an issue for my cold morning start ( low idle on startup unles i touch the throttle pedal then it picks up and its all normal)

have found genuine sensor for s14 nothing r33 specific unless i pay $$ from nissan. so would s14 be same?

part number seems same as r33?

if anyone can run it in fast or knows it would be great

$80 from nissan

Coolant temp sensor for ECU and gauge (they are separate) are at the front of the plenum, just before the water outlet to the radiator.

Some info that I have gleaned:

RB20/26 use a yellow sensor.

RB25 uses a brown sensor (different resistance to RB20/26, when I ran a brown sensor with RB20 ECU it thought it was in cold start all the time).

RB25 Neo uses a blue sensor.

Coolant temp sensor for ECU and gauge (they are separate) are at the front of the plenum, just before the water outlet to the radiator.

Some info that I have gleaned:

RB20/26 use a yellow sensor.

RB25 uses a brown sensor (different resistance to RB20/26, when I ran a brown sensor with RB20 ECU it thought it was in cold start all the time).

RB25 Neo uses a blue sensor.

the yellow sensor has been superseded, nissan now give you a blue one if your chasing a new one, been told it suits a few different nissan motors

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