ESP light on a 03 AVB passat

diarmaid21

Ok so I have a 03 1.9tdi Passat. AVB. A while back the ESP light would come on occasionally (maybe every second day), and the engine would start stuttering very badly, not drivable at all. I would have to pull over turn her off, and when I’d turn it back on again she would be fine, sometimes I might have to restart her up to 5 or 6 times before she was ok again… A mechanic told me that it’s a sign that one of the injectors is on the way out. I put that injector cleaner through the diesel and it seemed to cure the problem for about 4 weeks. Right after using the cleaner the car had less power- This was then diagnosed by the computer- Bad MAF. But now the bad stuttering and ESP light are back, but now more frequent, it now happens almost every time I sit in the car.


So I guess my question is; has this happened to anyone before? Is it definitely an injector problem, or could it be the wiring harness, or anything else?? A huge thanks in advance for any feedback!

George Dalton

Sounds like the injector wiring harness.

diarmaid21

Hi George,


Thanks for your response, that’s also what I suspected myself as it seems to be a more common issue with these cars. Is there a way of double checking this before replacing? Or do I just replace and hope for the best?

George Dalton

They usually leave a pretty definitive fault code when they are faulty.

diarmaid21

So the code can’t be mistaken for bad injectors? Is it unusual that no fault code related to injectors came up when it was tested a few days ago? (the car was ok at the time, but not 4 weeks before hand, or two days after…)

George Dalton

In general, a faulty loom will leave an electrical circuit fault code, whereas a faulty injector will log a misfire code.

It is unusual that there were no fault codes relating to injectors logged when the scan was done.

diarmaid21

That makes sense to me now, thanks! , it wouldn’t leave the house at all this morning, after restarting her about 10-12 times she was still the same – stuttering so bad you couldn’t drive her… I tried again there about an hour ago, and still the same, even after another 10 restarts.. so I left her running and emptied the last half bottle of that injector cleaner into the tank, left her ticking over for about 5 minutes, revving a bit at times, then after I restarted she seemed perfect!! Drove her about 8 miles, and no bother at all on her! It’s this same bottle that made it stop last time too,, so in that case does it sound more like the injector?

George Dalton

Could be, but also could still be the loom.

Vw2003

I have a passat, same year and sane engine code and the exact same issue, except mine doesnt be that bad that ya couldnt drive it. I replaced de wiring harness wit a brand new one and it cured the problem for about three days and now its as bad as it was. Im starting to wonder was the harness i got faulty or perhaps damaged when fittin cos its an awkward job and requires the loom being bent to get it in.