Earth Wire Problem

Dear All,

I have an Audi A2 (Reg: 2003), FSI. The car has low mileage for its age and I have not had many issues in my short period of ownership (3 coil packs have been replaced and there has been a heating issue). Hence my surprise when I had a Service earlier this year and I was told the water pump needed fixing. This I did, and the car has not been the same since. The first thing I noticed after the Service, was that the ignition was not functioning as it should. (Instead of it turning on normally, I now have to press down the accelerator to get the engine started.) Secondly, a few weeks after the Service, the engine management light came on. I took the car back to the mechanic who had performed the Service. He replaced a coil pack, and then after the problem persisted, he told me that there was a problem with the wiring (the earth wire).

I am now at the stage where I have had 3 different professional opinions on the matter. The mechanic who performed the Service, told me to see an Autoelectrician. The Autoelectrician performed a diagnostic and tells me there is either a wiring problem or a CPU needs replacing and in order for him to find out, I will need to spend another £800 or so for him to find out. (He suggests that I dispose of the car.) A third mechanic advises he can find out the problem for a few hours labour. Importantly, none of them have been able to put their finger on the problem, even though all of them have performed a diagnostic on the car. Seeing as I purchased the car with good money, I am reluctant to get rid of it at a substantial loss. I am also reluctant to pay huge costs for the repair of the vehicle. Part of me suspects the diagnosis may be wrong, as different professionals have said different things.

What do people on the Forum think the problem is? Has anyone come across this type of problem before? In your experience of Audi A2's, what advice would you give going forward?

I would be most grateful for your replies.

Thank you in advance.
First thing I would do would be to get a VCDS scan and see what codes it is throwing.

Where about in the country are you? I am sure someone can help you out

Do you have any warning lights on?

You can clean the earth points up yourself, search the forum for locations, one behind the headlight area and one on top by coils.

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Well-Known Member
Just picking up on the problem which happened after the water pump replacement. Pure speculation but this would involve removing the cam belt, and if not set up accurately could cause the timing to be slightly out of spec and even screw up the correlation between the cam and crank sensor output signals. Both issues would contribute to difficult starting. (I'm assuming the engine spins over fine but is reluctant to fire up)
I think your nearest A2 Specialist will be WOM Automotive - They know their stuff and won't rip you off so I'd be tempted to ignore the random diagnosis from the other garages and talk to WOM.

Cheers Spike
I would second Spike suggestion about the cam timing being out, particularly as starting was difficult after the water pump was replaced, simple replacing the pump would make no difference to the starting as the relationship between the crank and the cams was the same as it was before the water pump was replaced, it is quite easy to get it a tooth out if the mechanic did not have the correct tool to align the cams and also knows where to align the crank for TDC. It would certainly be a fairly easy thing to check or have checked by someone in the know, only involves removing the top cam belt cover to perform the check (from memory)

Hi there,

Thanks for your reply. Yes the engine management light system is on and has been on for the last few weeks.

I am based towards Manchester.

Thank you for your suggestions and advice.
Hi Mike and Paul,

Thank you for your posts. This was the same point suggested by the third mechanic I mentioned above, although he would like to spend up to half-a-day with the car to investigate further. What I don't understand, though, is how the Autoelectrician and original mechanic who performed the Service, both could have missed this?

I am very grateful for your help and recommendations so far. Thank you very much.

Thank you
assuming that the original mechanic did the water pump/timing belt change it is possible that the mechanic did not realise that the timing was a tooth out, particularly if he did not have the correct cam alignment tool, so not really acceptable, but certainly possible.
The auto electrician would not necessarily have the skill set to pick this up, as he is more concerned with sensors, ecu's, wiring (all things electrical) and therefore a basic mechanical problem would not be on his radar, having said that the ECU may well be complaining and poping up fault codes as there will be a correlation between the crank sensor and the CAM sensor that will be incorrect due to the timing belt tooth out issue.
It sounds like the third mechanic is on the right path, but I do think that half a day to diagnose if the CAM timing is correct is some what excessive, I would have thought an hour max as from memory once the top cam belt cover is removed (a couple of spring clips) there is access to the CAM sprockets and therefore the crank can be rotated to TDC and then check if an 8mm pin slides in the alignment hole in each of the CAM sprockets and into the holes in the cylinder head.#Now if the CAM timing is incorrect then there is more work to do to correct it as the lower CAM belt cover needs to be removed to access the tensioner which needs to be slackened off in order to remove the belt(s), re position the CAM sprockets in the correct alignment and then refit the belt(s) and re tension the belt(s), this is likely to be half a day (as to remove the lower belt cover the engine mount must also be removed, and the engine supported from underneath)