Mass Airflow Sensor failure 996 - K&N???

2000 Millenium Edition 996 - TPC Supercharger - K&N cone filter. This set up has fried 2 x MAF sensors. The Porsche dealership says it's the oiled K&N filter. Anyone else had a problem like this? The stock airbox is gone from the TPC installation. The dealership has said they have run into problems with K&N filters (the oil) on other customers cars killing MAF sensors. Any solutions???? Thanks. Gheers! GL

That's the word on the street. The oil is contributing to the MAF failure. Not sure what those with the K&N are doing to avoid it. Maybe some with the K&N can chime in. I know there are several guys on the board with SC'ed cars.

Check out some of the V-Flow threads on 6speed the guys at evo have figure this one out I beleive. They are using an oil free filter I think or something along those lines.

Here is a fact, You can soak the entire MAF in motor oil overnight and then clean it it the morning and the readings of all sensors will be the same as before you soaked it. Oil will not damage the sensor, but only make them less sensitive because of contamination. Clean the MAF and put it back in. I have yet to see anyone on this forum that complains about a MAF being bad put any effort into diagnosing the problem by maybe looking at the sensor readings before throwing it away. These are not some mysterious electrical componant. They are quite simple and other than physical breakage or excessive voltage spikes, they are not going to go bad. If you use an oil soaked filter, you should make cleaning the MAF as part of regular maintenance. When you change the oil, clean the sensor.

I have a KN, but i dont oil it...No mas air problems yet..

Are you saying that you didn't put any oil on it after buying it, or that you cleaned all of the oil off? Oiled filters are well known to cause MAF failures in the 996, and in any other car too. Just clean it off with electronics cleaner and you should be good to go.

The K and N needs oil to filter properly. The secret is to follow the oiling directions to the letter. Excess oil is the usual reason for contamination of the MAF. Oil lightly and let the oil dry overnight before using the filter. The directions are explicit.. follow them and no MAF problems.

I've put K&N filters in every car I've ever owned since the 1970s. I have late models of a Honda with 135K miles, a Lexus with 30K miles, and my P-car with 25K and no MAF problems in any. I don't think it's fair to say "well known" and "any other car". Just be careful about over-oiling and let them sit for a day or in the sun for several hours.

yah... what arenared said. I've had my K&N in their for 3 years... haven't oiled it yet cause it's still "pink" - the color of the oil... if you take it out and inspect it you will where most of the air comes in.. a perfect round spot (on right hand side) above where the air gets sucked in... this area will not be pink because its filtering most of the air... its is perfectly white... in this case I would just flip the airfilter around so the "pink" area of the filter is below the hose that goes into the air... if you do oil it... don't apply too much... 2-3 passes at most and let it sit for a full 3 days before re-installing... also you want to spray the bottom of the filter and *not* the top... make sure to wipe of excell oil with a clean cloth before re-installing...

The old sensor WAS cleaned with an electronics spray cleaner...then put back in. Same readings...Check Engine...ABS/PSM lights on...would not clear. The NEW sensor was put in...engine was run.....NO LIGHTS ON. Cleared everything. So...how do you explain that? What am I doing wrong? The old sensor lasted 3 weeks before crapping out. So if it ain't the oil contaminating it...what's frying them or what can be done to stop the dash lighting up like a X-mas tree? Cheers! GL

What was the readings of the old MAF and what is the readings of the new one? Electonic cleaner quite often will not remove the carbon on the hot wire and will therefore, not properly clean the sensor. I generally use either starter fluid or carb cleaner. Edit: In your particular case with the TPC blower, you have to make sure that they have adjusted for the increased current being produced by the increased air going past the MAF. If this was not properly done, you can put in a new MAF everyday and will still have problems. You have to look at the readings of the MAF.

The bigger question is why mess with the K & N to begin with? Oiled filters are no better (maybe worse) at filtering dirt than paper filters, and it's easy to pop in a new paper filter when the time comes. There is also no performance gain relative to paper filters. I'm talking here about filters for the standard air box, I'm not familiar with what options are out there for cone filters.

I think from what I have seen on my car that K&N gives you somewhat better throttle response and breathing.. not that much... but for $100 its worth it... also cleaning your K&N too often is not recommended.... the dirt built up is an important part of an effective K&N cleaning system...

K and N filters work fine...but the benefit is negligible IMHO. I use a standard paper filter and change it twice a year and at the same time I clean the MAF. If you do use a K and N oil lightly...BUT in all cases make cleaning your MAF part of your regular maintenance of the car. I clean mine twice a year and it works fine and has worked fine for a number of years. Clean with a good electronics part cleaner that is gentle on plastic or even plain rubbing alcohol...then I use canned air to dry the unit. Its good advice and simple to do as 1999Porsche911 says.

How do you obtain the "reading" off the old MAF and the new MAF? What is involved in that...and can I do it myself??? Cheers! GL

Cone filters do not come in a stock un-oiled "paper" form to my knowledge...they all must be oiled. K&N filters and any other Cone filter that is oiled comes "pre-oiled" from the factory. I have to use a non stock air filter since the TPC supercharger eliminates the Factory Airbox. Cheers! GL

Get youself a scanner that will display the various readings of the sensors. O2, MAF, etc. Only by having the ability to see what the sensors are actually doing can you begin to diagnois the problem. Typical response by a dealer is replace, replace, replace. If you went to the dealer because your alarm system didn't work, they would replace the MAF.

My dealer advised against a K & N for the very same reasons cited in the first post. He claims they have seen several MAF problems/failures in cars equipped with K & N....most were DIY, and were done incorrectly to begin with.

I called K&N to get an answer about there filters and if they have had problems with 996 MAF sensors....the Service Rep said he had heard of these problems...asked how much money had been spent on replacing MAF sensors...stopped talking...and IMMEDIATLEY wanted to put me over to the Claims Dept. I left a message. We'll see what happens. Cheers! GL

Ok, I want to start cleaning the MAF since I use a K&N Filter. How should I do that? Remove the MAF clip from the rubber tube that goes to the throttle body and spray it with either starter fluid or carb cleaner? Anything else need to be done?

Nope. That's it. For regular cleaning, using electronics spray cleaner will suffice.

mine went out at 25k miles-no k/n filter-wasnt that expensive to replace

Let me add that I have a non-K&N 996 with just 20K on it, and my MAS has crapped out. I cleaned it, replaced it and it still triggered the codes. So I installed a new one, cleared the codes, and now I can't pass emissions inspections because the "readiness" codes have not reset or something, despite 45 miles on the clock. Anyone have any experience getting emissions inspection completed. How many friggin miles do I have to drive to reset the computer? Porsche told me 5 to 15, but that was obviously wrong because I failed at 45 miles. Well, didn't actually fail, just aborted because the computer was not "reset" despite the fact the codes had been cleared. Ahhhhhhhhhhhhhg.

Depending on what year car, it is not he miles that reset the compuer monitoring, but the number of drive cycles. Everything should be ok after 2 - 3 cycles.

Yeah, what does a new MAF cost?

I just bought one from Sunset Porsche for around $270.00.

$270 is a great price, they're usually closer to $350 from a lot of dealers!

Well....I'm at a total loss now. The K&N filter was taken off completely and replaced with a custom made paper/foam filter with no oil....the MAF crapped out again!!!! Sumpin ain't right. Could the Computer that was installed for the Supercharger be frying these things by accident...a wiring short....anyboby have any suggestions to what it could be...Bueller...Bueller...Bueller??? Cheers! GL

I had the same problem when I changed my cone K&N on my Evo SC. Todd told me to soak the new filter in soapy warm water then air dry and not re-oil. He does that to all his instals. I have had no trouble since. My expirence with cleaning the MAF has been it only helps temporarily and then the problem recurrs. Perhaps with the increased air flow of forced induction it draws more oil out of the filter onto the MAF. Also remember the MAF changed slightly from 2001 to 2002 so check the numbers closely. They will work but the car will not run right. I know everyone will say the filter does not work as well without proper oiling but that is just the way it is,and Todd at Evo will agree. Will

What are the readings of the MAF? Have you hooked up your scanner and looked?