Mass Air Flow Sensor

[DoubleNutz]

How much is the MAF? I have heard time and time again that it is expensive and difficult to DIY it and have yet to find these details when doing a "search" here. I have heard that the price of a MAF is different C4 and a C2.

I have heard all kinds of junk on this and have seen no real collective agrement or answers.

Good question though- Can a MAF be cleaned? I am concered becuase I keep getting this P1130 code "check engine lite" and I have already changed the 02 sensor, the bellows tube looks fine and I am beginning to think it maybe the MAF and I cannot, for the life of me, figure our why that bastard went bad.

If it is a bad MAF then I would like to do the repair myself and am uncertain if there is something i need to know before doing it. There is NO info on DIY of MAF repair, change, diagnostics anywhere. :(

[Loren]

Here is my 2 cents worth...

Sorry, I can not give you the prices because I don't have them.

Here is what I can tell you --

* Through MY01 there are 2 MAF sensors -- one for non e-gas cars (MY99 C2's) and one for all cars with e-gas (which includes MY99 C4's). MY02 cars all have e-gas so there is only one (yet different) MAF for them.

* If you only have a P1130 code without the P1128 code then that signifies your problem is on one bank of the engine. Here is what my Pcode list says: P1130 Oxygen Sensing Adaptation Area 2 (Cylinders 4 - 6) - Rich Threshold. Fuel / air mixture is so lean that sensing has reached it's rich thershold. Probable causes are listed as: Intake air system leaking; Fuel pressure too low; Volume of supply fuel pump too low; Fuel injectors fouled.

I think I would start looking for any loose or worn vacuum hoses around the intake area. Consider changing the fuel filter. See if you can borrow an MAF from someone to rule it in or out.

Finally, I had the dealer replace my MAF under warranty -- twice -- before they realized that the connector on the DME (behind the rear seats) had come loose. So, the MAF's were likely okay. You never know, it could be something easy and even dealers sometimes jump on the MAF too soon.

Changing the MAF is pretty simple. There are two special screws that hold it in place. I'll check the tool tomorrow and add to this post.

Update: August 25th -- it is a Security Torx with Center Pin -- as David said, basically a Torx with a hole for the pin in the center.

p.s I merged your two posts as they were pretty much the same.

Edited August 25, 2003 by Loren

[David (Va)]

FWIW they changed the MAF twice on my TT. I was told the Bosch units aren't that great. The readout on the PST2 said MAF failure. ( the ABS/PSM light came on at high boost)

The cost on the invoice (still under warranty) was listed as $119.00, which Porsche picked up.

BTW I checked and cleaned it after the first one went. I used a torx screwdriver I drilled the center out with a small bit to fit in the little raised point in the center of the screw.

[Eric (Plug Guy)]

Another issue: I had my CE light come on recently, and based on the fault code the MAF was replaced. CE light came back on. After lengthy investigation, it was found to be a bad Bellows Tube.

The MAF replacements was in the $450 range. The bellows tube is about $20 and takes a good tech around 30 minutes, but the book says 2 hours labor charge.

[gery]

Eric,

What is the story with WarrantyGold? Are they paying for anything on this ocassion?

[sharkster]

Blast.. my CEL comes on (then I reset it) with both the 1130 and 1128 codes:( I've got straight pipes with 100 cell cats (from Fabspeed), a BMC air filter, a slightly dremmeled airbox and modified turbos etc...

[gery]

What is the size of secure torx?

[Loren]

What is the size of secure torx?

I beleive it is a T-20 Security Torx.

If you can't find it locally, then you can get one here for about $2.20 (LOL -- $10 minimum order).

[Flakarter]

You can buy a small set of the tamper proof torx bits at Autozone or Napa for $15-20. AMHIK.

Dean

[gery]

need a pic of where and how to replace MAF.

Thanks in advance

[Loren]

need a pic of where and how to replace MAF.

Thanks in advance

Unplug the sensor (Item 3 is the sensor). Remove the two T20 security Torx screws (Item 4). Replace the sensor and tighten screws. Plug electrical connection back in.

[Flakarter]

Loren, should the negative battery cable be removed before unplugging and replugging the MAF sensor?

If so, will he need the radio code after the battery is reconnected?

Dean

[Loren]

Loren, should the negative battery cable be removed before unplugging and replugging the MAF sensor? 

If so, will he need the radio code after the battery is reconnected?

Dean

No. Just to be safe keep the key out of the ignition.

[gery]

thanks. Great help as expected. Why does the dealer quoted me 1 hour of labor? 30 mins for screw?

[Loren]

thanks. Great help as expected. Why does the dealer quoted me 1 hour of labor? 30 mins for screw?

Usually most dealers (and shops) have a 1 hour minimum charge. I guess it's overhead :rolleyes:

[gery]

Try to swap MAF into MY99 with one from MY00 and struck out. Diffrent clamp types. Now I need part number for MY99 so I can scavenge internet...

Help

[Loren]

The part number for all C2's (without egas) from 98 through 99 is 996 606 123 00. My guess is you got a C2 (with egas) or C4 MAF which is 996 606 124 00. They are definitely different.

Just an FYI the MAF for all MY02 and newer is 996 606 125 01.

[gery]

MY99 is C2 cab and other car was MY00 C2. Wires connection to MAF are done using rectangular plastic connector. The clamps for wires on MY99 are are on the narrow sides, while MY00 C2 has a single clamp on wide side....

[Loren]

MY99 is C2 cab and other car was MY00 C2. Wires connection to MAF are done using rectangular plastic connector. The clamps for wires on MY99 are are on the narrow sides, while MY00 C2 has a single clamp on wide side....

All MY00 C2's would be egas cars... so the sensor is different.

[ebaker]

The BMW forum recommended cleaning The mass air sensor using simple green and alcohol. Has anyone had any luck with this?

[karlooz]

i have used non residue forming electrical contact cleaner with great success on my (s)old boxster. all you have to do is spray on all parts metal and let dry. no need to use cotton swab,. just let the solvent do its work.

[msindi]

karlooz - do you know what the name of the solvent is and where to get it?

[Fern]

Try an electronics hobby store like Radio Shack...

Or any automotive parts store will also carry it.

Refer to it as electrical contact cleaner- the non residue type... :D

[my996]

need a pic of where and how to replace MAF.

Thanks in advance

Unplug the sensor (Item 3 is the sensor). Remove the two T20 security Torx screws (Item 4). Replace the sensor and tighten screws. Plug electrical connection back in.

<{POST_SNAPBACK}>

How do you unplug the MAF? I thought it would just disconnect but it does not. I don't want to pry too hard. Am I missing something or should I just yank at it?

Edited May 28, 2005 by my996

[umn]

...

I don't want to pry too hard.  Am I missing something or should I just yank at it?

...

Don't yank at it. It's clipped in, so you need to press the little release at the side of the plug to pull it out.