Interesting read on Bosch maf

[wayneg]

MAF Sensor Repair In Depth - Expedition Portal (http://www.expeditionportal.com/forum/threads/31752-MAF-Sensor-Repair-In-Depth)

I have just tried a Merc one in my car and it runs fine

[wayneg]

Well after reading all the stuff on the Porsche guys using VW Mafs and me running the RR on a Merc one I decided to see how cheap I could pick one up for to have as an emergency in the car.
$20.89c inc shipping got me a shiny new VW / Audi model complete maf unit from deepest China .
I took out the insert from the VW housing, stuck it in the RR and she runs sweet. I will leave it in to see how it goes over a few weeks. I will be keeping the original in the glove box just in case.

[wayneg]

It has not taken long to come to the conclusion that although the car will run pretty well with a random Bosch insert things are not 100%. On one occasion on start from cold the idle was all over the place, I felt the engine was being over fuelled. A couple of times in slow traffic I have had hesitation on acceleration.
Original back in and 100% again.

Lessons learnt.
If you are in dire need any Bosch insert with the correct plug type should get you running for as long as you need. Emergency fix only.

Of course the $20 Chinese unit was always going to be suspect.