The car wont idle when cold.

I have warmed the engine to running temperature and adjusted the air screw on the throttle body and the screw on the ECU and the engine idled well when hot, but since then it will not idle when cold and cuts out if its nor revved, I have spayed brake cleaner into the engine bay to check for air leaks but I cant find any.

I need to get the idle working well and the idle CO down to under 4,5% to pass the roadworthy test.

Anyone got any ideas on what to do?

I can't remember the build details on your car. Stock D-Jet?

Check the Aux Air Valve to see if that's open when cold. Sounds like you're not getting enough air. Also worth verifying your CHT is working within specs, and timing is correct.

+1 on checking the AAV.

When cold, pull the hose that goes from the air cleaner to the AAV (at the air cleaner end) and you should be able to blow air into it and through to the plenum/manifold. If not it's stuck shut and there are threads here re: how to try to un-stick it.

Might also check for a clogged PCV valve but I'm not sure that would have an impact if the AAV was working.

Ron

Thanks guys I will follow your advice.

I forgot to mention that the car is a 2.0 with stock D Jet with 2056 P & C

I just looked at mine and need to clarify - on my 1.7 that hose from the air cleaner to the AAV has a "Y" in the middle of it with another hose providing fresh air to the decel valve. So when you blow into it the air goes both places. The decel valve should be closed however so with a stuck AAV you should not be able to get any air to go through.

This is all from my 1.7 so yours may be a bit different.

Ron

I have checked the AAV and it is open when the engine is cold, I also checked the timing and it seems good.

What else would cause the engine not to ideling properly (die when cold), and what is the procedure for adjusting the bleed screw on the throttle body and ECU knob?

Thanks in advace.

Dave,

Since you are in Sweden, how cold are we talking about? Fahrenheit please////

What is your AFR at cold and warm idle? If it's too rich, the AAR may have little effect. Check your cold start valve and thermo time Switch.
And echoing what Rob said: verify your CHT is working correctly.
Also read through this if you haven't done so already: D-Jetronic Parts Analysis and Troubleshooting

For adjusting idle, after warming the engine up I use the TB screw to get the idle at around 900=1000RPM and then turn the knob on the ECU as far counter-clockwise as I can get it without the idle hunting. (Clock-wise richens the mixture). Aim for within a few clicks from the middle setting.

Today was around 64 F (18 C), not cold a nice summers day.