Herman K

When I experience any of these conditions (I first check for any vacuum leaks with a MYTY-VAC)provided there're none) I hook up the hammer and with the engine at normal working temprature run it through the engine adopter test cycle during this process you can hear the related components being activated and being de-activated at the end of the cycle she'll idles steady and on the money if any of the components fail the cycle will not complete and indicate the one you need to check out

John Speake

The LH is programmed to give a slightly higher idle speed when water temp is below normal operating temp.

But then it should settle down to 675rpm for an S4.

the flyin' scotsman

Temp II check, at the sensor.

Engine cold............readings of 4.5k - 5k ohms
Engine would not start with the sensor disconnected. Fired right up after reconnect.

As the engine warmed the resistance levels decreased as they should but after reaching temperature that engaged the rad fans the resistance levels were both in the 250 ohm range. The WSM states resistance of ~100 ohms at 100C.

Given the test results I'm inclined to believe the sensor is working but slightly out of spec?

I also took the opp. to spray the ISV (WD trick down the hose)...........no change. Checked cables.........all good.

Idle remained solid at 1k rpm.

John Speake

Temp 2 spec at 100degC is 100-210R so yours sounds OK.

Sounds like an airleak...

the flyin' scotsman

Thx John, appreciate the input and your PM.

We're at the time of year when every driving moment is precious before mother winter truly arrives and the car is garaged for 3-4 mths.

I'll try to provide more analysis asap as I'd like this out the way before playing with the new LH, PEMs and ST II