Fixed Idle issue

[t_marat]

I had problems with idle. Shift to neutral at anything higher than 1000rpm and the engine rpm would go directly to 0. Thought it was an issue with my ICV. Had it cleaned two times. Changed the intake manifold gaskets. Did not help.
Decided to change the ICV. Bought a used one off Ebay.de together with a new MAF. I was pretty sure my MAF was dead.
As fitting the MAF is much easier than the ICV, did it first. And amazing, I have no issues with idle any longer!! It is very steady and the car now pulls a little better.
Before this, engaging a fan blower to full power (or anything putting a strain on the engine) would lower the idle. Now, swiftly turning the fan to full power leads to a little idle drop, but the idle almost immediately rises back to its original level (maybe a little higher).

Never thought/read that a dead MAF would cause idle problems. Maybe it's something to do with the Siemens ECU that is in my car?

[BillionPa]

the MAF meters the air into the car, all the air!

so at idle, if the MAF is dead, the fuel mixture is WAY OFF!

and as such, going from idle will be pretty shaky

[t_marat]

My expectation was that the "limp home mode" should have a stable idle.

[BillionPa]

limp home mode is not very accurate at metering, and only works "acceptably" when the O2 sensors are tip top and at operating temp.

[t_marat]

Thanks.