Idle RPM

[Eskozki]

maybe my late cars ICV is not working properly, but I usually find that if I defeat the ICV by using the wire at the plug, the car won't idle at high enough RPM when the engine is warm enough for the radiator fans to kick in. So I often adjust the idle with the ICV in play afterwards to a bit higher idle speed. I checked that applying 12v to the valve makes it move like it should so atleast it is not stuck.

[Monkey Wrench]

Originally Posted by originalowner

It bypasses the throttle but not the afm. The dme enriches the mixture based on temperature.

so as temp varies so does the open time ( dwell) of injectors. compensating for the cold .. it proves how important that 944 temp sensor is and how it relates to idle speed. I have to wonder if a new temp sensor or even cleaning it may change his idle speed.

a common trick in cooler climates is to put a hunk of cardboard over about half the rad. better for the engine not to struggle a long time just to warm up. my 66 volvo had an option of a pull chain with what looks a lot like an upside down window blind so you can adjust it when driving.. it's a simple solution for a faster warmup if you are currently driving in cold weather. grab half a pizza box, stick it in front, then keep an eye on your temp gauge. it'll warm up a lot faster and put out more heat to clear the windows.

The cooling system is designed to work in the hot temps.. In cooler temps it is too much rad for the cooling needs.. if the rad core plugs up it makes the rad a lot less efficient. - similar effect. Just don't forget you've added it and overheat it.