will a bad MAF Sensor cause shifting problems? 03 Passat W8

[W8 Victim]

I unplugged my MAF sensor a few days ago and the engine is running fine. BUT,,, On my way to work I felt and heard a loud BANG! twice on seperate ocasions while driving like 40 MPH or coasting from that speed. Really scary stuff. The thransmission also shifts hard into drive. Sometimes reverse.

Why is this happening?

I hate electronics when I don't understand what is happening or if I don't have the proper equipment.

The bang was so hard it feels like someone rearended me or like a loose cardan axle

[davenay67]

I can't help you, but I can say I am experiencing similar problems. I did a spark plug and air filter replacement service a couple of weeks ago, and during the fitting of the new air filter I must have pulled too hard against the MAF wiring harness....net result is that I pulled a wire out. Ever since then I have been experiencing hard downshifts from 5th to 4th.

As coincidental as this is, I can't believe that the MAF would cause this particular downshifting problem. It's just been tool cold to do anyhting here in Chicago lately, but this weekend is much warmer and I am planning to solder in a new MAF woire tomorrow. I am hopeful this will help, but I am not expecting it to do anything to help to be honest.

My next step is to get a VAG-COM scan and see if that highlights any particular fault codes. I am expecting to have to send my transmission valve body away for rebuild.

My car is a 1.8T by the way.


Dave.

[W8 Victim]

wow. Then I am suspecting a MAF problem. I thought I knew everything about cars. I even owned an Audi A8 and never had problems.
I read somewhere that the transmission is computer control and I know this ZF transmissions all have a TCM. But I want to confirm if it needs MAF data to shift properly.

Shit

[davenay67]

I can now confirm that the MAF can absolutely cause bad shifting. As I mentioned above, my car started slamming the 5th to 4th downshifts after I broke a wire in the MAF. After repairing the MAF wire this morning, the car instantyly starting shifting as smooth as silk again. Weird, but I'm not complaining....especially as I though I had an expensive and time-consuming repair on my hands.

Not saying it is your problem, but the MAF might be a problem. Even the VW dealer I spoke to hadn't head of this, and didn't think the MAF could be the cause of my bad shifting. Just goes to show how much they don't know, despite charging big $$$$ for service..!!


Dave.

[W8 Victim]

I can now confirm that the MAF can absolutely cause bad shifting. As I mentioned above, my car started slamming the 5th to 4th downshifts after I broke a wire in the MAF. After repairing the MAF wire this morning, the car instantyly starting shifting as smooth as silk again. Weird, but I'm not complaining....especially as I though I had an expensive and time-consuming repair on my hands.

Not saying it is your problem, but the MAF might be a problem. Even the VW dealer I spoke to hadn't head of this, and didn't think the MAF could be the cause of my bad shifting. Just goes to show how much they don't know, despite charging big $$$$ for service..!!


Dave.

Thank you for your input. I agree with you now. A faulty Mass air sensor affects the ZF5hp Transmission. it's computer controlled. My transmission made a violent slam while doing around 45mph and this only happened when I unplugged the MAF. Also feels sluggish and shifts hard into drive and sometimes reverse. Soon as I plugged it up, shifts smooth but the engine runs like crap and burns rich on Bank 1.
Strangest thing I ever seen. I hope I didn't break anything.

Where can I buy a Mass Airflow Sensor? My autoparts store locally gave me a price but they can't order it. Dealer only item supposedly.

Does anyone here have one for sale??? I looked on ebay buy they all claim that their MAF sensors will also fit the 4.0 w8. I doubt all trims have the same air sensor.

Is my car's MAF sensor specific or can I use any Audi or passat of the same year. Even say's a 2005 tourage's MAF will fit a W8.
Can someone provide a link to buy a MAF for a W8 ? thank you so much for your input.

[RosevilleWgn]

http://www.ezvwparts.com/ appears to have them for the 4.0 for $156~, OEM.

[W8 Victim]

Hey! I noticed you're from Naperville. I worked out there last year for three months doing contract work for American Recovery Act fiber project. They set us up in a hotel in Westmont. I remember walking all over Naperville areas and loved the little parks with the trails. little town just west of Chicago. I was shocked they even had a Banco Popular on 35 I think it was. That's my bank and I was impressed. Yes siree, I remember Naperville real well. Lots of nice homes and great sidewalks out there. I drove to Chicago on my day off cause I never been there and it started turning ghetto east of Westmont. Uglier and uglier as you go east.

[davenay67]

We love Naperville in the spring and summertime, when we can stroll around downtown and take the kids to the water park. An awesome little town to raise a family. Only downside is that it's far away from most everything workwise. My current commute is a ball-busting 100 miles a day right now.

The price isn't quite as good as the poster above, but ECS Tuning has a really nice service; great website, good prices and very helpful guys.

http://www.ecstuning.com/Volkswagen-.../Mass_Airflow/


Good luck with the fix....the W8 is a nice car.


Dave.

[abonilla951]

lol funny.. i have a few friends that live in naperville .. and yea they drive a long way to work lol

[knutlovhoiden]

hey guys,
i've had a similar problem with rought shifting and a loud 'jolt'.
I was (and still am) getting a MAF code, even though i replaced the MAF when i discovered that i had the code. car stills shifts hard. any suggestions?

[W8 Victim]

hey guys,
i've had a similar problem with rought shifting and a loud 'jolt'.
I was (and still am) getting a MAF code, even though i replaced the MAF when i discovered that i had the code. car stills shifts hard. any suggestions?

I hope this doesn't happen to me. If you bought a new MAF sensor and you are 100 percent positive it works, try checking for vaccum leaks. Any little cracked house will set off your MAF sensor. That much I know.

My problem is that I don't even have a MAF sensor malfunction code.

But in our case, if mass air flow meter is bad and causes shifting problems,
Then based on your info (you have a new MAF and still getting shift problems)
You have a vaccum leak. I would think that any air not getting past the flow meter is giving false reading to ECM

I am learning as I go, take my theory with a grain of salt.

Oh, I forgot to mention, Clear all your codes after installing new sensors. Keep clearing them as you drive to make sure it's not running on old info.
This may help...I had an Audi A8 and I forgot that you could reset the transmission computer by turning the key and pressing the gas, but I forgot the sequence.

[davenay67]

hey guys,
i've had a similar problem with rought shifting and a loud 'jolt'.
I was (and still am) getting a MAF code, even though i replaced the MAF when i discovered that i had the code. car stills shifts hard. any suggestions?

What code are you getting..?? As soon as I accidently broke my green MAF wire, I was getting a P0102 code. Identify your code, determine the problem and go with the appropriate fix.

Soldering in a new wire and clearing the codes solved my issues. I am still scheduled to do a ATF and filter change when the weather allows me to lay on my back for more than just a few seconds and my hands not go numb within minutes of being outside..!!


Dave.

[W8 Victim]

Today I went to the local junk yard , Winter Haven Florida and pulled a mass airflow sensor off a 2005 Tourage or something. The part numbers are exactly the same.

I paid $50 bucks cash and went home in my truck to test this MAF sensor on my W8 Passat.

It ran a little rough at start up, I cleared the old codes and restarted.

My car is running like a brand new 2011 Audi, so smooth and quiet now. No lights

I drove the car 40 miles so far and it shifts like silk has power and not a hiccup.

In the begining of this problem, My car never threw a code for a bad mass air flow sensor. It threw 02 sensor code, catalytic and missfire codes. And all this time I just had a faulty sensor that wasn't reading right.
Car runs like a dream. Very quiet cabin. Feels like a brand new car at the dealer. Can't hear the engine at all. Feels like the car is off. I am not exaggerating none of this. This stupid little problem would have cost me like $700 total at the dealer. It is worth the investment to get a VAG scan tool in my opinion.

[davenay67]

Glad all is well for you now....gotta love it when a fix that you are dreading will cost $$$$ ends up costing just $50.

Dave.

[knutlovhoiden]

What code are you getting..?? As soon as I accidently broke my green MAF wire, I was getting a P0102 code. Identify your code, determine the problem and go with the appropriate fix.

Soldering in a new wire and clearing the codes solved my issues. I am still scheduled to do a ATF and filter change when the weather allows me to lay on my back for more than just a few seconds and my hands not go numb within minutes of being outside..!!


Dave.

thanks dave,
I'll check the connector since i too am getting the p0102 code.


victim - i did break a vacuum line but i dont know which one it is, or where it went. i'll look into it more when the weather in MI gets warm...

[RosevilleWgn]

Car runs like a dream. Very quiet cabin. Feels like a brand new car at the dealer. Can't hear the engine at all. Feels like the car is off. I am not exaggerating none of this. This stupid little problem would have cost me like $700 total at the dealer. It is worth the investment to get a VAG scan tool in my opinion.

Aren't these cars awesome? I know the 30V feels wonderful (smooth idle, plenty of power) but I can only imagine the W8. Granted, neither are quite as fun as the 360 Spyder I drove once (Don't ask how I avoided a ticket at 140mph), but I'd rather own the Passat for day to day.