I have picked up a strange fault after steam cleaning my engine .
I know it is not such a good idea to do so with all the plugs etc , but have done before without issues. I used to take car for a drive afterwards , this time did not.
The first problem I encountered was on startup, the rev counter would fully deflect as the starter is cranked, and the Engine management light would stay on.
I will drive, and the engine will just cut. Switching off/on ignition would have the engine start immediately, but rpm no higher than 1400 , with loads of smoke if throttle is added. Engine Mngement light on.
I opened all the plugs I could get to on the battery side, blew out with air, and all mentioned issues are cleared.
I am however stuck with a curious issue. When the engine is started from cold , all is fine , engine smooth ( well , diesel smooth

The weird thing is , Yesterday I started up , drove to the highway and drove for 65Kms non stop, sometimes up to 130 kmh. Lots of power , no smoke , perfect. I made sure not to let go of the pedal completely when traffic slowed down , but used brakes to regulate, so it was partial power on all the time.
As soon as I stopped at the first turnoff, and let the motor idle with no pressure on the gas-pedal, the problem was back. No power , 1400 rpm and smoke .
So , my question is, is there any control which is fully deflected and unmoving with throttle input when the motor is below operating temperature , but then has to deflect with throttle input when the engine is on normal operating temp?
Are there other hidden plugs I should look at, or could it be a vacuum issue?
Anton