# Car runs better without MAF sensor???



## josemolina2008 (Mar 8, 2011)

So a while back my CEL and EPC light came on shortly after putting an intake in my car. I pulled the code and was told I needed a new MAF sensor. Car ran good without the MAF just smelled rich. Bought a brand new sensor and it ran great for about 20 min and then started acting really weird. When I would rev the car and then let off it would sound like it back fired kind of like when an exhaust pops from the two step. Then I would have very minimal power and take forever to climb rpms. I pulled over and turned off the car. When I started it back up it idled funny then shut off. It would keep doing this till stayed on the gas and drove for a bit and it would be rough till I got to the higher rpm range. Then when I got home the revs would alternate between about 750 to 1000 and all of a sudden boom CEL and EPC light came back on and car ran normal I am stumped on what it could be and I don't have a code reader at the moment to see what popped up. Any help would be greatly appreciated and as soon as I pull the code(s) I will post them up. BTW the car has about 148,000 miles if that helps.


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## 03gleye (May 8, 2010)

People still run mafs?


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## Jo|\| (Jul 3, 2011)

Have the O2 sensors ever been replaced?

I had a MAF fail a while back and after I replaced it my car ran like crap. It turned out it and been dying for a while but the way it was failing canceled out bad O2 readings. So when I replaced the MAF the car was getting faulty readings from the O2 sensors so it ran with a bad air/fuel mixture.

The reason the car runs better without a MAF is because the ecu falls back to set values when sensors are unplugged. With the MAF missing it runs rich, since lean can trash the head/pistons.


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## josemolina2008 (Mar 8, 2011)

Yeah the O2 senser went out a while back and I replaced it, this was the one before the cat. I bought a VAG-COM cable and I'll run a diagnosis on it when it gets here. Hopefully I can get this fixed because its getting on my nerves


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## josemolina2008 (Mar 8, 2011)

Ok well the car is going crazy now the EPC light goes on and off and when it turn off the car runs like crap and when it goes on it runs good.  Can't wait for the cable to come in so that I can take a more in depth look into things!


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## 24vGTiVR6 (Sep 14, 2010)

I dunno what it is with 24v's, but I've had to replace my MAF 4 times already in ~3 years, and Ive seen other posts sayin the same thing...... I could've put that $ towards a standalone with MAP 

I'm just gonna delete the bloody thing as soon as I can. Why are OEM MAF's so freakin fragile?

gl op, and yah once you get the cable it should be pretty easy to diagnose.


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## 02JttaGLI (Nov 23, 2010)

24vGTiVR6 said:


> I dunno what it is with 24v's, but I've had to replace my MAF 4 times already in ~3 years, and Ive seen other posts sayin the same thing...... I could've put that $ towards a standalone with MAP


are you running a stock airbox with a paper filter?


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## 24vGTiVR6 (Sep 14, 2010)

02JttaGLI said:


> are you running a stock airbox with a paper filter?


dry filter (non oiled) in a 4" housing connected to a kinetic inlet pipe to the turbo


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## koko5869 (Feb 15, 2006)

24vGTiVR6 said:


> I dunno what it is with 24v's, but I've had to replace my MAF 4 times already in ~3 years, and Ive seen other posts sayin the same thing...... I could've put that $ towards a standalone with MAP
> 
> I'm just gonna delete the bloody thing as soon as I can. Why are OEM MAF's so freakin fragile?
> 
> gl op, and yah once you get the cable it should be pretty easy to diagnose.


Buy 2.0 mafs and save yourself a ton of money. They use to only be $99 from performance cafe I believe.


Op, leave the maf unplugged until you get vag com and get a chance to scan it. 
It'll run rich because itll be on closed loop, but at least you don't have to worry about it bucking or stalling or anything in the middle of an intersection. 

Sent from my HTC_Amaze_4G using Tapatalk 2


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## josemolina2008 (Mar 8, 2011)

Still waiting on the cable :thumbdown: and yeah I disconnected it for the same reason, it would run good then all of a sudden start bucking and have no power which is embarrassing on take offs from a stand still


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## josemolina2008 (Mar 8, 2011)

Well cable came in today but since I have Windows 7 I cannot get the full version of VAG-COM to work  I would need Windows 7 Premium or Ultimate to be able to run the program as it would in Windows XP since that's what it meant for. I got the lite version of VCDS though and it spit out these three codes: 16497, 16486, 16523. The first is "16497 - Intake Air Temp. Sensor (G42): Signal too High P0113", when I get a chance I'll make sure the connections are good and if that's not it look into getting a new one. The second code is "16486/P0102/000258 - Mass Air Flow Sensor (MAF/G70): Signal too Low". Its brand new so I'll be checking the wiring to it and see if the connector is good. Hopefully its not a bad one. And the last code was "O2 sensor: slow response, Bank 2". This is a newer sensor, probably like five months old. I was reading that if the MAF is out for whatever reason that the computer will show low readings in the second O2 sensor. Hopefully this is so and I do not have to replace the O2 sensor also. As for the air temperature sensor not reading right what problems could that cause? Sorry for the long essay just want to get this thing figured out since my tags need to be renewed and I need to smog it and pass 

Here's what the VCDS Lite spit out for me:

VCDS-Lite Version: Release 1.1
Tuesday, 13 November 2012, 23:28:29.


Chassis Type: 1J - VW Golf/Bora IV
Scan: 01,02,03,08,15,16,17,19,22,29,35,36,37,39,46,47,55,56,57,75,76

-------------------------------------------------------------------------------
Address 01: Engine  Labels: 022-906-032-BDF.LBL
Controller: 022 906 032 BM
Component: MOTRONIC ME7.1.1G 0004
Coding: 00032
Shop #: WSC 00001
VCID: 57C1085FA603
9BWPH61J924064413 VWZ7Z0B4877757
3 Faults Found:
16497 - Intake Air Temp. Sensor (G42): Signal too High
P0113 - 35-00 - -
16486 - Shareware Version. To Decode all DTCs
P0102 - 35-00 - Please Register/Activate
16523 - Shareware Version. To Decode all DTCs
P0139 - 35-10 - Please Register/Activate - Intermittent
Readiness: 0000 1101

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: Redir Fail!
Controller: 1C0 907 379 G
Component: ESP FRONT MK60 0101
Coding: 0019970
Shop #: WSC 00000
VCID: 2E2F8DBBF919
2 Faults Found:
00285 - ABS Wheel Speed Sensor; Front Right (G45)
012 - Electrical Fault in Circuit
01314 - Shareware Version. To Decode all DTCs
013 - Please Register/Activate

P.S. The ABS stuff is just a wire that got worn down by rubbing against my wheel, it will be fixed soon.


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## Jo|\| (Jul 3, 2011)

josemolina2008 said:


> Well cable came in today but since I have Windows 7 I cannot get the full version of VAG-COM to work  I would need Windows 7 Premium or Ultimate to be able to run the program as it would in Windows XP since that's what it meant for.


VCDS supports Win7. I'm running it on Win 7 Home Premium. There is no need to run in it XP compatibility mode. If you bought a real ross-tech cable just contact them for support.

Log block 2(maf airflow in g/s) at WOT from idle to redline and see if it's registering the correct air flow. I have a couple logs to compare to. 

Also check block 4 for the air intake temp.


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