Re: MAF update for those interested

I am throwing some codes that point me to a bad MAF. Issue is this MAF only has 7 to 8K miles on it. This is only the 3rd MAF I have put in and my car has 165K miles on it.
With this few miles on this MAF compared to the first 2 could I be looking at another issue that looks like a bad MAF or do some go this quickly? I cleaned it 2X but codes come back.

98 2.5L 165K miles

Right now P0102. When I erased codes recently was getting P1124/1126/0102- I have not put many miles on and first code to come back was P0102.

but I am still getting the 0102. I would like to hear what answers you get.

I cleaned mine twice but codes come back. Cleaning is a hit or miss thing- First time I had codes pointing at MAF many years (& miles ago) I cleaned it and no issues for almost 2 years after that.

Are you getting any other syptoms aside from the code?

Quote
Ollie
I am throwing some codes that point me to a bad MAF. Issue is this MAF only has 7 to 8K miles on it. This is only the 3rd MAF I have put in and my car has 165K miles on it.
With this few miles on this MAF compared to the first 2 could I be looking at another issue that looks like a bad MAF or do some go this quickly? I cleaned it 2X but codes come back.

98 2.5L 165K miles

get dirty enough to generate any problems and require cleaning unless you're running some oil it yourself aftermarket airfilter system. (With the stock filter in place, and changed (sort of regularly -- whenever I think about it which is about every 2 years -- my car's MAF has never required cleaning. A MAF in a properly filtered air intake system just doesn't get dirty.)

The P0102 error code is an artifact being triggered due to a problem unrelated to the MAF. The error codes (ignoring the P0102) point to an air leak.

For an intake air leak, the first thing that comes to mind is the AOS unless you tell me this is relatively new.

Next I recall I replaced a perfectly good MAF with a new one only to find out the real cause of the symptoms (mainly error codes) was a leaking oil filler tube cap. Check this with the engine up to temp, at idle, move it around to see if it is loose and if you can hear any air leaking past/around the cap and its seal. Or the cap is cheap enough you can just replace it. (Unless the coolant tank cap is new (at least it does not have part # the ends in '00') replace it too with a newer cap. Of course you remove the coolant tank cap only after the engine has cooled completely down.

If you find the cap suspicious, or even leaking, replace the oil filler tube cap and clear the codes and drive the car. Since the problem may be a going bad AOS be careful that at the first sign the engine is getting 'sicker' shut off the enigne and avoiding running it any until the cause of the symptoms can be identified and fixed.

Sincerely,

MarcW.

Not argueing here just talking through this- I looked for obvious air leaks as I agree 1124/1126 can be caused by leaks, oil cap seems fine, radiator cap new this year. Pumped some smoke in looking for leaks could not find anything or hear anything. AOS has 28K miles on it- have no obvious smoke typical of AOS failure & and pulled connection and see no oil build up typical of a failing AOS. Stock air filter approx 2K miles ago. pulled a couiple of plugs and they clean/dry of oil.

I am not sure what else to check... Seems that a bad MAF could indeed cause issues defined for 1124/1126

P0102- Mass Or Volume Air Flow A Circuit Low Input
P1124 - Manufacturer Controlled Fuel And Air Metering
P1126- Manufacturer Controlled Fuel And Air Metering

Quote
Ollie
Not argueing here just talking through this- I looked for obvious air leaks as I agree 1124/1126 can be caused by leaks, oil cap seems fine, radiator cap new this year. Pumped some smoke in looking for leaks could not find anything or hear anything. AOS has 28K miles on it- have no obvious smoke typical of AOS failure & and pulled connection and see no oil build up typical of a failing AOS. Stock air filter approx 2K miles ago. pulled a couiple of plugs and they clean/dry of oil.

I am not sure what else to check... Seems that a bad MAF could indeed cause issues defined for 1124/1126

P0102- Mass Or Volume Air Flow A Circuit Low Input
P1124 - Manufacturer Controlled Fuel And Air Metering
P1126- Manufacturer Controlled Fuel And Air Metering

Before you do any fuel flow/pressure tests though one 'trick' is to disconnect the MAF at the wiring harness and clear the codes -- clears the long term fuel trims which may have been derived from data supplied by a bad MAF -- and drive the car as you would normally.

If after say 30 miles or so of just driving if the error codes do not appear, reconnect the MAF, clear the codes again, and drive the car again. If the codes appear... MAF.

Be aware the CEL may come on with the MAF disconnected so do not assume if the CEL comes on it is due the same error codes as before. Be prepared to read the codes. Also, check the long term trims to see if they are on the high (positive side) which is a sign extra fuel is being added to adjust for a lean mixture. With the MAF out of the loop then this strongly suggests the MAF is not at fault.

Sincerely,

MarcW.

I did have a bad AOS but got that replaced and drive it like I stole it for a bit but then it came back on.

... I had always wondered why there was such a big discrepancy in pricing between what the dealer charges and what you can find a genuine Bosch (with the same Porsche part number) on the internet.
I mean, for my car, part number 996.606.123.00, the MSRP is $611.96, but I can find it online for only $193.95!
The Dealer sells it for 3 times more money!
So, I decided to investigate why this big difference.
Speaking to a high-level Porsche AG source who shall remain anonymous, he told me why.
When Bosch manufactures any part with a Porsche Part Number on it, it can only be sold from the manufacturer (Bosch) to Porsche.
Porsche then tests each Mass Airflow Sensor individually, keeping only the ones that pass their rigorous tests.
The ones that fail are then sold to the aftermarket vendors.
Some of these may fail by the smallest of margins, so they would be a great buy, but others are completely off the charts so they fail almost immediately upon installation.
Generally a dealer-sold MAF will last a looooooong time, while the aftermarket ones seem to have a much shorter life span.
And, as Paul Harvey used to say.... now you know the rest of the story.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Interesting- Being an engineer in the Microelectronics industry I can understand the extra testing & cost impact- especially when you consider the large counterfit market within the electronics industry right now.

Yesterday I found the web site below. It lists Bosch OEM for $215. It also has Aftermarket New MAF for $94 and a remanufactured MAF for $66 plus $15 core. All with a 12 month warranty. At least they are not trying to sell the aftermarket units as OEM. This is the first time I have come across aftermarket MAF's. Kind of interested to see if these really work and how well they were reverse engineered !!!!

[www.carpartswarehouse.com]#

Cleared the codes and headed out for 50 mile trip to buddies 98 that is in storage for winter... P1124 & P0102 back on within 4 miles. I have shut the codes off 3X and pop back on within 5 miles.of driving each time.

Swaped known good MAF in & have put on 70 miles with no codes.

Going to order new MAF and see what happens but looks like MAF is the issue

I think you have pretty much confirmed this time it is the MAF.

And thanks for the update.

Sincerely,

MarcW.

I've got a question. For $600 bucks, aren't there plenty of folks out there who would just disconnect the battery and let the CEL go out, and just forget about it until it comes back on.

I did that 18 months ago, and it stays off until last week.

I can't get too energized about a freaky light. It reminds me of what Churchill said: Never before have so many people toiled so hard, spent so much, and accomplished so little.

OKAY, I'm kidding, and I am buying a Code Reader to get to the bottom of my CEL issues, but, still, something seems out of whack with the money and hassles on CEL problems.



P.S. Any idea how much money the dealer rake in over this issue?

Quote
kentv1
I've got a question. For $600 bucks, aren't there plenty of folks out there who would just disconnect the battery and let the CEL go out, and just forget about it until it comes back on.

I did that 18 months ago, and it stays off until last week.

I can't get too energized about a freaky light. It reminds me of what Churchill said: Never before have so many people toiled so hard, spent so much, and accomplished so little.

OKAY, I'm kidding, and I am buying a Code Reader to get to the bottom of my CEL issues, but, still, something seems out of whack with the money and hassles on CEL problems.



P.S. Any idea how much money the dealer rake in over this issue?

computer controlled engines (and other systems) having a warning light that lets you know something's amiss (often times the light comes on and there is no other symptom or sign of any problem) and then being able to read some numbers that with some research points one towards the possible cause of the CEL and code is better than the alternative.

The light comes on for a reason. It might be a leaking gas cap or it might be something much more serious. Whatever it is knowing why it is on is half the battle.

Sincerely,

MarcW.

Quote
Pedro (Weston, FL)
Generally a dealer-sold MAF will last a looooooong time, while the aftermarket ones seem to have a much shorter life span.

And something I wish I had read a month ago!

On a recommendation from another forum, I bought this one for $90. Appears to be working as intended. But, according to your informant, may not last as long as an OEM Porsche marked one.



Edited 2 time(s). Last edit at 01/23/2012 06:48PM by bar10dah. (view changes)