A4 B7 3.0 TDI Quattro Faults P3348 P0638 P1571 ESP Light not working, Juddering when Accelerating


Registered User
Hi All,

New to the forum so thanks for having me.

Im having some pretty frustrating probems with my 2005 A4 estate 3.0 TDI Quattro Automatic at the moment, I've had it in the garage and under diagnostics too and they are a little confused so wanted to ask around before i start throwing too much cash at it.

It all started with the ESP light coming on and off intermittently over the past year, it wasnt really causing any problems and i wasn't in a position where i could fix it as I was working in france at the time (language barriers and french mechanic prices are not ideal!)

The car then developed a problem where it would judder when accelerating at lower speeds around 30mph and between say 1600-1900 revs, but if i let off the pedal for second it would ease off and also once i exceeded these revs/over 30ish mph it would smooth out again, that being said it is a pretty violent judder that seems to me through the steering wheel. Possibly ABS doing something weird?

I am now at the point where the ESP light does not come on at all, it doesn't even register when I turn the car on, pressing the esp button/holding it in etc does nothing...I dont particularly care if the light comes on or not but I am pretty sure it is linked to the overall problem.

Every now and again the ABS light / Brake warnings will come on but brakes/pads and discs all seem fine.

Sometimes on long journeys the car will flash with the PRNDS in red but still drive absolutely fine on the motorway. (drove 1000km back from france a few weeks ago with no problems other than the juddering at low speeds)

The car also failed its MOT on emissions, it seems like quite a lot of white smoke coming out of the back, I wondered if this may clear with a good drive though, it has currently been turned on and off a lot to check for faults and not really being driven, just sat on the drive.

I have been doing a lot of reading and tried to replace/fix the cheaper things that it could be, I have replaced brake light switch, cleaned and checked the MAF sensor and also replaced the MAF connector which was definitely broken but doesn't seem to have fixed anything, also all brake sensors seem to be OK...these are all basic problems people have reported that i have investigated myself.

So i finally took it to the garage and they have pulled up a few more codes which point to more serious things and require a fair bit more money spent on them we have also had an auto electrician look at the car and rule out any wiring/connector issues.

The codes that are now coming up are:

P3348 - Control Circuit for controller for turbo charger
P1571 Main electrical circuit relay elec malfunction
P0638 Throttle Actuator Control Range/Performance B1

The garage are suggesting the throttle and/or turbo may need replacing but not 100% sure yet and they are a bit stumped so i wanted to ask on here first!

Does anyone have any ideas?

Main problems are the juddering when accelerating and emissions...then obviously engline light being on which has caused the MOT failure!

Thank you all in advance, im not too clued up with cars but working with the garage to hopefully find a solution!