Cold idle stalling issue. Warm restart OK!?

[CMF_sotheby]

G'day team.
I have an SLX auto CVT. Full Whiteline performance handling kit, Hurricane 4-2-1 and 2" mandrel bent exhaust. Also British PiperCross foam panel air filter. Otherwise, all stock. The car has about 126,000km on the clock and has been running fine for the 6 months I have owned it . . . until now:

Upon a cold start (car garaged overnight) it tends to get very close to stalling when driven a few hundred metres. Being an auto I have to come to a dead stop, slip into 'N', rev hard a couple of times, click back to 'D', and carry on ;-) Over the weekend I have:

1. Performed the complete throttle body resolder operation, including use of additional solder. The IC card looked OK, but I resoldered anyway!
2. Completely cleaned the Idle Control Valve unit, until it was sparkling like almost new!

I have always been running the car on 95RON Caltex 'Vortex'. This fuel comes with engine cleaner dissolved in it. Several months ago I put the $20 Nulon fuel/injector cleaning treatment through the fuel tank.

The funny thing is, when the car is warm to hot, restarting and running are not a problem - ie. the throttle body and engine are warm. It's only cold starts that present a problem. I now let the car run for 2-3 minutes before driving off in the morning. The dash doesn't have a tacho, but my fine hearing tells me initially the car seems to sound 'correct' when starting from cold - ie. high revs., before tapering off. Any ideas anybody? I'm ordering the Haynes book through Ebay UK, and I speak Russian so I'll also be downloading the Russian maintenance guide as well ;-) If I need a new TB I can get new ones relatively cheaply from the UK, thanks to the strong AUD. All help appreciated! Cheers.

 

[CMF_1300cc]

according to haynes, if it jump starts when its cold, u have a problem with battery, or does it start, its jus the idling which is not correct..i was also thinking of the sensor responsible for the cold starting....just cant remember what is called.

 

[CMF_1300cc]

ive got some time today....so found this .....

I am assuming it cranks OK. I suspect the idle air control (IAC) solenoid is sticking. This is very common and it happens more in cold weather.

I want you to try this the next time you suspect it will crank, but won't start. Hold the throttle at about 5 or 10% while cranking. If it starts, but dies as soon as you release the throttle, I want you to try the next step. With an assistant, open the hood, locate the IAC solenoid. Crank the car while the assistant taps the IAC, it should start and operate normally. If it does, replace the IAC solenoid with agenuin

 

[CMF_frank2]

sotheby WROTE:

car seems to sound 'correct' when starting from cold - ie. high revs., before tapering off.

the coldstart waxstat at the back of the t/b should hold the revs at about 2k, and slowly release over a few minutes
so if thats working ok it should,nt be trying to stall after a few hundred metres

 

[CMF_sotheby]

Thanks folks for the quick responses! The car always fires up without issue, then runs at high idle (as intended). After about 2 minutes or so the idle drops dangerously low until the engine warms up . . . then it's fine again. I'll be changing the fuel filter tonight. I have found some suspiciously similar hits on some British forums, and the 'CTS' - Coolant Temperature Sensor is mentioned several times. It's under $40 at SuperCheap. I might try changing this sensor after I've tried the fuel filter swap. The filter looks like very old.

 

[CMF_asdame]

if the IAV is working fine, just up ur idle speed screw so that it idles at 700rpm when warm and fast idle when cold

 

[CMF_sotheby]

Over the weekend I thoroughly cleaned out the throttle body and MAF sensor with carbie cleaner. The car starts a little easier in the morning. I have a Tridon Coolant Temperature Sensor on order with SuperCheap - $28. Nissan quoted $122 - on order from Japan. According to Nissan, there are zero stocks in Australia. They are a joke. My mechanic will change this sensor and also the fuel filter. Hopefully these actions will yield results ;-)