Clean the MAF first, its simple and only takes 15 minutes. I had the same thing on my 2001. I had cleaned and oiled my K&N and then had the lights come on as I came off the freeway with the hunting idle. The shop said it was a blow MAF and put a new one in (after prutting stock filter back in). Problem fixed, but after reading the MAF cleaning threads, I cleaned the old "blown" one and put it back in. Runs fine with no adverse affects, in fact the new MAF must have been getting dirty (about 3,000 mi on it) as the old one actually did a better job just off idle.

 

You MAF is done. My most recent (986) MAF lasted 4 days. I've heard there is something in developement. Let's keep our fingers crossed.

 

Well, some updates...took the turbo into Pacific Porsche here in the South Bay and there were 2 problems. First of all, I've got to hand it to you guys that contributed on this thread...most of you were right on the money on at least half of the problem. MAF failed and so they are replacing it AND the found a broken boost hose going to the diverter valves. I'm PRAYING that this actually solves the problem and more importantly, that my extended warranty covers some of this ****. I'll keep you all posted...

 

By the way, they did mention that the aftermarket air filters (I have a B&M air filter) have an oil that coats the MAF causing failures. Sounds like Brokenleg has encountered the same problem (see below). Do you know if this is typical to have the aftermarket air filters (B&M, K&N, etc) cause problems with the MAF? Also, does the EVO V-Flow Induction System also have an oiled filter or cause problems with the MAF? I may have to upgrade to it if I continue to have probems with my MAF.

 

Just for the record a new MAF and my problems were solved.

Does anyone have a view on buying a MAF from Bosch for around half the price of the Bosch MAF via Porsche?

 

Try this to see if maybe there isnt a more basic "root cause" for these MAF problems. Clean the terminals of the MAF with rubbing alchohol and a Q-tip, then a light coating of "contact oil" or other dielectric media, reconnect and test.
I suggest doing this even before you clean the MAF, my reasoning behind this is; I believe the contacts are the root to many of these MAF issues, when what you are accomplishing is simply to "renew" proper contact during Maf replacement.
I am factory trained for VW/Audi and Porsche. I have seen far fewer MAF problems, than this "cross section" would suggest I should have, so....
Before you throw the baby out with the bathwater....
A simple observation.
The real way to determine if your MAF is bad isnt with a "Ouija" board, but a scan tool, and the ability to read grams per second in airflow across the meter. For a given car, with a given gearbox (auto/vs stick) there is a range of airflow (g/sec) specific to the vehicle.
Compare, and save! (couldn't resist).
Anyway your car, and your Buddy's car should have close to the same #'s, for the same gear, same rpm's...
Until next time...thats my story, and I'm sticking to it!
Jay Putnam, a.k.a. "Jayster".

 

Yes the aftermarket Bosch units are different, from the ones at the dealer...
They come in a different colored box, and they cost less...
So technically they arent the same, so if that bothers you ...(LOL)... get the real one!