Idling problem, please help!
 

Hey everyone,

I'd have a big problem, which I hope, you could help to solve. I've got an Escort from 92' in which I've put an 1.8 Zetec engine from 99' with an EEC-V engine control unit. My problem would be with that there is no "choke" when the engine is cold. I mean that after a cold start up and 5 secs, the idling is already 900 and the engine is stuttering. In this case, the performance is quite small, too. As the engine warms the idling becomes smoother and the performance is getting better. There is no error code. The ECT sensor works properly and there is no broken cable. What I did is the changing of IAC valve.

Thank you in advance for your answers.

The electronic version of the "choke" is performed by software based upon the temperature measured by the ECT. This will include enriching the mixture and raising the idle rpm.
It looks to me if the ECT sensor is giving out a wrong (too warm) signal.
Hookup a diagnostic reader and you can check this temperature.

Basically that was the first thing I checked. I mean, the ECT. I've even changed it to an other one which was surely working. The resistance of the sensor was the same as I had in the ECU. I've tried to get live data, too but could not connect to the ECU.

Do you maybe know what tool does the ECU communicate with? What protocol does it support?

Thanks!