Hey everyone,

I've owned my 03 996TT for about a year now and love it. The only issue I seem to have is I will be coming to a stop (I think every time this has happened it has been coming to a stop) and the ABS/PSM lights will come on and the idle will stumble a bit. It first happened about a month into ownership and I just turned off the car and when I restarted everything was fine for a bit. Clearly though it would continue to happen every time I drove the car and I only drive it maybe twice a month. So I pulled the Durametrics out and that is where I found the code P0102 Hot Film MAF. I decided to try and clean it first before replacing to see if it made a difference and it did. I was able to drive 100 miles or so (a few trips) before it would happen again. So I cleaned it one more time really good with CRC MAF cleaner, and I was really thorough. Low and behold it stayed off for six months and 1100 miles. I actually forgot about the problem until it popped up again on my last drive. Knowing the cleaning kept the issue at bay for that long and that many miles I decided to order a new MAF (I researched and got the correct one with the right part number OEM 996 606 124 00). I cleared the code, installed the MAF and took it for a drive. It came on faster than ever before, almost right away, I didn't even get out of the neighborhood, and I noticed when it was warming up it felt like it was running a bit different (rougher) than it should with the new MAF. So I came back, and cleaned my old MAF again very thoroughly again with CRC and installed. Car ran perfect, and I took it for a 13 mile loop and all is well again. I checked the MAF values with Durametrics while idling and they were 1.4-1.5 V and 22 hg flow which seems normal from what I've researched. I'm thinking, maybe the MAF I got was no good, but it also seems strange that it would cause the exact same code and not throw something new. Anyway not sure what the next step would be so thought I'd ask for some advice here. I'm thinking of just seeing how long it goes this time with my freshly cleaned, old MAF back in. If it goes another 6 months, 1000+ miles I'm guess the new MAF I got is just bad. I know other things can cause this issue, from boost or intake leaks, vacuum leaks, to broken wires or even a bad brake light. I feel like if it was a leak of some kind it would not have gone away for so long by cleaning the MAF. Also I feel like if it was something like a brake light, or electrical not sure why it would cause the idle to stumble and throw the Hot Film MAF code. On all the other threads I came across (a bunch of them) it seems like they all had multiple codes, I just have always had the one code P0102. My gut says it is the MAF and I just got a bad one and to reorder another to be sure, but wanted to ask you experts what you thought first. Thanks for any help.

 

 

^^^ Sorry forgot to put that, no, it is stock filter, no oily residues. Just took it on another 15 mile loop to grab dinner, ran perfect. I'm thinking of switching to the new MAF just to see if it comes on again but I don't think I would trust it after throwing the lights/code the first time it was installed. That is the problem with getting a new part and then not suspecting it is "bad", it is the classic "red herring" scenario. Wish I knew someone with the same car and I could test a known good one.

 

Is a hard reset of the ecu required when changing to a new MAF? Would that cause the issue to reappear right away like it did? If so, I did not do that, wasn't sure if it was really needed or not so I guess I could try that before sending this one back as defective?

 

If you are using durametric, it will clear the fault. Also disconnecting the battery for a time will clear the faults. Are you sure the one you bought is "real"?

 

Yeah, I cleared the fault with Durametric, but was researching and found a few posts where people had mentioned that pulling the negative cable for a few minutes is different than just resetting the fault and is required when changing a new sensor. I wasn't sure it was or not so thought I'd ask and see if anyone knows 100%. Also, yes the part numbers on the Bosch I received are identical to the OEM coming out of the car. It was around 200.00, so far less than the 800-900 the dealer charges (my word what are they thinking??!!!) but that is the going rate for OEM bought from places like ECS, Pelican other suppliers, etc. for the same unit. During my research on buying the 2-300 part vs the dealer part I came across a thread that said the reason the Porsche Dealer one's are so much more is because they rigorously test each unit to make sure it is within tight specifications. I can't see how this adds almost 400% but oh well. Maybe there is something to it though, meaning these cars need absolutely the best of the best? Anyway that is another thread I guess. The place I purchased it from was very nice and said I could send it back no questions asked but if disconnecting the neg. cable for a few would fix the issue forever I would hate to send it back without doing that if you know what I mean. I hate disconnecting batteries though b/c how much other crap is going to have to be reset if I do that. I know of the radio codes (although not sure that was an issue in 03+) but what other things may have an issue by completely discharging the ECU's power?

 

There is no battery disconnect required if you cleared the codes with durametric after you replaced the MAF. I understand the PN is on the MAF, but the question I am asking is: Is that a bosch MAF, or is it a knockoff? The knockoffs also have the correct PN on them. Compare the replacement to the original that you swapped. Is it IDENTICAL? BTW, cleaning a MAF will not fix it if it is fried...

You have an '03, so radio codes will be saved when you disconnect the battery.

 

So I had a similar issue and purchased a new MAF on Amazon and just like you I cleaned my old one and it would work for a bit, but the new one threw the errors right away. I reached out to the seller and he said: "yeah these cars are sensitive and I have 20% failure rate with these MAFs despite being bosch etc.". So he shipped me another one and now all is well. Been good for over a 1K miles. See if your seller would do the same as mine.

 

Yes identical Bosch in sealed Bosch box. The company has a good rep so I don't see a bait and switch issue.

 

Interesting, that was my gut reaction as well. I"m going to return the new one and see how long it goes again before happening then will buy from another vendor if I need to, thanks guys.