MAF failure?Your expert opinions please.

[Mike McKinstry]

Hi Guys,

Just been to France for the half term and on way down M11/M25 after approx 2 hrs driving car lacked what I would describe boost ,struggled uphills and struggled to pull fast in any gear although drove smoothly enough-no guts like turbo packed up-foot to the floor and it is as if limited to 60mph!.
Tried switch on/off on hardshoulder and car started with boost but before pulling back out had died again .
After overnight stop car started and ran with full power until about 20miles from Paris (2.30hrs)where we lost power again making accelerating past slower traffic more dodgy.
Left 3 days and have just covered 340miles with 1 stop on tunnel with no problems.
Had similar 6/8 weeks ago accelerating up hill and cured switching on /off?

Do you think this is MAF failure and can this be intermittent or is it usually complete failure or do you think this is actuator?.I have not had opp. to unplug MAf or diagnose and feel VAGCOM will probably not show anything due to nature of fault.
Because fault is intermittent it will be hard to unplug MAF and recognise any improvement?
If turbo or MAF why does shutting off/on make a difference?.
Vehicle is 130PD with 141K now and has completed 3 continental trips this year -was goin to throw MAF at it -Pierburg?-but just wanted to check with the gurus first!!

Mike

[Brainscram]

I had exactly same problem last year in my 1.9TDI 1998, I changed the MAF with a compatable one from e-bay for about £35 , no problens since then.
I think they called the ebay shop "The air flow shop" or "The air flow meter company" or something very similar. Good luck

[happysnappy]

I had exactly the same happen to me . It will keep going into "limp mode" and switching off re-sets the system. Changing the MAF sensor worked for me but im told there are other sensors and pipes that could be a problem source. But the MAF is a very common cause, it cost me £32
and I fitted it in 30 mins max from opening the bonnet to driving away.

[tdi miki]

[?
If turbo or MAF why does shutting off/on make a difference?.
Vehicle is 130PD with 141K now and has completed 3 continental trips this year -was goin to throw MAF at it -Pierburg?-but just wanted to check with the gurus first!!

Mike[/quote]

First of all get your car scaned for fault codes.They will show up on VAG-COM because once the car has a code turning the engineoff will reset it but wont erase it .It has to be erased with diagnostic tool.The problem could be turbo related because if you have stuck vanes on the turbocharger they can not react as fast as they should so in some moments the ECU recognises that as an overboost and deactivates the turbo valve N75 so you lose power.Shutting it off resets the ECU and you have power bac untill next time it hapens.The thing you should do to diagnose the problem is to plug in VAG-COM and do a test run.If you suspect MAF go to measured value blocks group 10 and accelerate in third gear form 1500-3000 rpms. The field you should be looking is firs from the left where the readings for the MAf are.At 3000 rpms it should be at least 800 mg/h.
As for the turbo the procedure is the same only the mvb group is 11.There you have two values, specified and actuall. At 3000 prms devation of 100 mbars is deal,but if it is greater than 300-400 mbars there is your problem.

[Mike McKinstry]

Thanks guys,
Will get a VAGCOM check and keep you posted,
Mike.

[eugoogoly]

hi all. came across this thread and tried what tdi miki mentioned and was wondering if those values for the maf would be the same for a tdi110 afn engine. I was getting roughly 400mg/str at 3000rpm in third.

[Clive]

Hi there,
I think My Passat 1.9TDI130 may have this MAF problem. I haven't worked on cars for a few years and things seem to have moved on. Any idea where on the car I would find the MAF sensor? There seem to be VAG-COM leads available on ebay. Any idea where the Connector is on the car?
Any help appreciated.

Clive

[Baron_Samedi]

The OBD connector is mounted in the dashboard under the steering column.

[Shaz12]

My car few a weeks ago had an identical probelm in that it could not go over 60 mph on the motorway if their was a slope/gradient. When I checked this forum everyone seemed to be talking about MAF sensor failure etc.

I took my car to the garage and the mechanic quickly spotted the problem which was a tear on the inner side of the fat rubber pipe from the intercooler to the top of the engine. This was causing the air to escape and when engine was pressed it couldn't perform. The pipe was replaced and the problem was fixed. I would check this pipe on your car before shelling our for sensors.

[jack71]

my 2002 130 tdi se has started to go a bit sluggish,basically happened overnight.car runs fine,but on hills it feels a bit sluggish,and normal driving feels a bit chuggy as if there is a restriction.does this sound like the MAF also ?or something more sinister? had timing belt changed at 80,000miles,when is the next change due on it also?

cheers folks:1zhelp: