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I am slightly concerned...

My car has recently begun blowing the slightest bit of smoke at idle... It looks black... which I spose is better than white..

Also the car doesn't idle very well when warm.. when its cold it has a nice smooth idle, but after it warms up it is constantly hunting.

At around the same time I cut the speed limiter wire (No. 53)

I know that wouldn't have anything to do with it, but I am also thinking maybe the harness isnt plugged back in as tight as it could be??

I will check the harness later, but I thought I'd ask you guys what you think..

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There are 2 coolant temp sensors.

One for the dash and one for the ecu.

The one for the ecu controls coolant temp injector enrichment.

Have it reading cool all the time and it will be fine when the motor is cold but bad when the motor is warm. As you said, a little bit of black smoke on idle.

Most likely the afm, but still worth the look if its not.

Edited by Cubes
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https://www.sau.com.au/forums/topic/91500-smoke-and-idle/#findComment-1649998
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interesting.. I swapped the rhs one on mine a couple of months ago and no diff so I just figured that probably wasn't the problem.. maybe i should investigate too :P

I think I may have narrowed mine to old fuel pump though.. now inplace is a GTR one, problem seems to have gone in 20 mins of testing tonight.

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https://www.sau.com.au/forums/topic/91500-smoke-and-idle/#findComment-1650027
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its definitely the LHS connector.. you are right... pays to check the service manual :P.. Diagnostics are on page EN-384 of the RB20DET service manual if you have.

If you have a multimeter you can measure whether they are in spec..

I have tried most things but mine has always been a bit over the shop.. seemed better with the pump though (lack of fuel at low revs?). I'm off to clean the *proper* temp sensor right now... see whether that clears it up totally.

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