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sofapriest
13-02-2008, 11:05 AM
Hi there,

I have an 01 GT TDi Golf with a problem or two. The coil light sometimes comes on hilst driving and stays on. Also, the ESP light tends to come on when I go over speed bumps. However, the main problem is that it seems that whilst I can drive on A and B roads with no problem, as soon as I go onto the motorway, it seems as if there is a rev limiter in action, and I can't seem to get it over 3000 revs. I can get speed out of it on the motorway if going downhill in 6th gear, but not otherwise. If I opull of the motorway and switch the engine off the proble rights itself, only to reoccur when i go onto the motorway again.

Are these problems linked, or are they seperate, and can anyone suggest what the solution might be?

i have taken it into a VW garage and they seem to think that it's the injectors. But I'm worried that all they have done is plug it into a computer, rather than actually driving the thing.

.....

I just spoke to the garage and they said that their diagnostic showed no fault with the MAF sensor- the only faults it came up with was a fuel sensor and one with increased resistivity on the earth wires to the injector. Does that ring any bells with anyone?

chris.fulton
13-02-2008, 12:49 PM
Firstly, welcome to the forum.

The glow plug light can mean any number of engine faults so its hard to say exactly what the problem is, although a common fault with the Golfs and Boras is a faulty brake light switch which causes the glow plug light to flash. Next time it comes on, press your brake pedal and get someone to check if your brake lights are working. The ESP light may be due to a faulty sensor. The best thing to do in this case would be to connect the car to a diagnostics machine and get the fault codes read which you say the garage has done, this usually will pinpoint the exact problem whereas a test drive may leave you with a range of possible fixes, so I think the garage did the right thing.

As for the power loss, it sounds as though either the MAF is faulty or you're getting turbo pressure overboost/underboost problems and the car is going into 'Limp mode'. If you do a search on the forum for limp mode, you'll find loads of posts with people having similar problems. One thing I will say is that considering you've already had the fault codes read then you should be able to work out where the problem lies. If the MAF is faulty then no fault code will be recorded, if the turbo is over/underboosting then a fault code will be logged saying something like "charge pressure positive/negative deviation". Hope this helps

sofapriest
13-02-2008, 01:00 PM
That's great, thanks. I did ask the garage and they said that the MAF would show on the diagnostic, which is a bit annoying. :zx11:Limp mode definitely would though, I would have thought.

The manual said that the ESP may be triggered by all the tyres not being of the same diameter, too. I did look , but it was dark. Can say that the distance from rim to edge of tyre is different. Can this cause the ESP to cut power to the engine?

chris.fulton
13-02-2008, 01:15 PM
Strangely enough, a faulty MAF normally won't log any fault codes at all even though it does put the car into limp mode.

Never heard of different diameter tyres causing ESP problems but suppose it's a possibility. Only way to find out is to check the tyre diameters next time you get a chance. ESP problems should log some fault code though.

Don't suppose you're hitting the speed bumps at enough speed to cause the front wheels to lift off the ground for a short time, this would cause the ESP light to flash.

sofapriest
13-02-2008, 01:24 PM
Thanks Chris. As I suspected, I was experiencing a "computer says no" moment from the garage. If only I could have this kind of conversation with the garage, life would be so much better. Thank mate.

And no i wasn't hitting the speed bumps that fast.


I'll check the tyres when I go to the garage tonight. Have to pluckk up the courage to tell the garage that the MAF fault doesn't show up as an error code. Why do I have to do their job for them?

chris.fulton
13-02-2008, 01:35 PM
Just make sure there isn't any codes about charge pressure positive/negative deviation as this would point to the turbo instead, otherwise there's a good chance it's the MAF.

Good luck and let us know how you get on

sofapriest
13-02-2008, 01:39 PM
I will, thanks. They listed the only error codes, so I think its safe to assume that's not the problem.

Been a pleasure talkning to you. Thanks for your help.

sofapriest
13-02-2008, 03:49 PM
Hi there,

you'll love this- I just spoke to the VW garage, and they told me that there isn't a MAF sensor on that car - a Mk4 2001 GT TDI. I am getting really confused now. Please help.:1zhelp:

chris.fulton
13-02-2008, 04:50 PM
Hmmm, that sounds like complete b***cks to me. My car is a 2001 MK4 Golf GT TDI 115bhp and I have a MAF, infact the only Golf's I've ever heard of not having a MAF is the 1.4L and possibly the 1.6L petrol engines. I would try a different dealers to see what they say or even a site like http://www.eurocarparts.com

One other thing you could try is search the forum for a user called Crasher and send him a private message with the details of your car and also the chassis number if possible and he'll check it out for you and get you the exact part number of the MAF that suits your car.

sofapriest
13-02-2008, 05:09 PM
I called them back and the guy said that he had been told by the woman who answered the phone that I had said a MAP sensor. I asked what one of those was and he said it was the same as a MAF sensor but for a petrol engine.

Even if that was the case, which I doubt very much, you would think, knowing that the car was a diesel he might have made the leap to thinking that I meant a MAF sensor.:confused::biglaugh:

sofapriest
13-02-2008, 05:11 PM
I had spoken to a guy in the parts dept of another VW dealer and he told me I had the AMj engine (115 bhp), and he quoted me a price for the MAF sensor.

chris.fulton
13-02-2008, 05:35 PM
You have the exact same engine as me and they definitely have a MAF because I have replaced mine. Think they cost around £70

sofapriest
14-02-2008, 11:43 AM
Did say that the "Technical coordinator" there told me that the woman on serving desk told hm that I had said MAP sensor. I asked what that was and he said that it is the same thing as a MAF sensor but or petrol engines? Is that a reasonable misunderstanding to make? They knew I had a diesel car, so they should have been able to make the connection that I was talking about the MAF sensor, surely?:aargh4:

chris.fulton
14-02-2008, 02:12 PM
Well you would think so but as I always say, assume nothing. Did you manage to get a new MAF in the end?

roadkill
14-02-2008, 03:01 PM
i have a golf tdi, i to i had a serious power loss, espically when going up any incline, reading all these forums to find out what the problem was and always getting the results that the maf was faultly, i spoke to the previous owner of the car a he had just replaced the MAF, still not knowing the problem i took it the vw dealership and the problem was my fuel solarnoid, and now the car can keep up with a gti on take of total diiference cost was near the £170.00 mark but well worth it