Smoke And Idle

[Josh]

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..

[R33_Series2Lover]

check the air flow metre

[Cubes]

Also check coolant temp sensor.

[Josh]

Why the coolant temp sensor? It still displays the temp in the car... Does it help towards determining the correct idle speed?

Will check the air flow metre soon.

[Cubes]

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 October 18, 2005 by Cubes

[Josh]

Where is the coolant temp for the ecu located? RB20 I'm talking here..

[Cubes]

Just off where the top radiator hose connects.

You will see two plugs. Disconnect one and see if the dash reads nothing, its obviously the other.

From memory the VL's run are the same temp sensor.

[Josh]

Ahk! Yeh I've seen those two... will have a look now...

[predator]

temp sender for the ecu is the one on the right with the single wire I think.

[Josh]

Yeh? I'm pretty sure I pulled the one on the left (facing the car) and the in car temp gauge was still going... Anyway the idle raised when I unplugged it..

[predator]

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

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.

[Josh]

Okay.. well earlier today I rejoind the speed limiter wire, just to ease my mind and that did f**k all.. So its not that at least - like I thought..

[Josh]

I'm also gunna run some injector cleaner through it too... Would you guys recommend against that?

[predator]

its definitely the LHS connector.. you are right... pays to check the service manual .. 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.

[Cubes]

Nulon total fuel system cleaner I think it was I used to use.

was $20 a bottle from memory.

[Josh]

Worth it cubes? The car does have a sloppy start and I read in your other thread that it can be caused by dirty injectors...

[Cubes]

Probably not.

[Josh]

Hahaha

[Josh]

Well I cleaned the air flow metre a bit and that seems to have helped, although it isn't perfect... will run that injector cleaner and see what happens..