HELP -Traction control and epc light limp mode

[Jonesy07]

Just on my way into work and these two lights came on and put the car in limp mode.

Pulled over and stopped the car, on restart they went off. Got just down the road to work and they have come on again. Called audi assist and they are coming out.

Anyone got any ideas on what may be the problem ?

Cheers

[pekingprawn]

My friends car did this last week, be interesting to know what the outcome is, good luck with it though.

[neckarsulm]

vacuum leak, prob from area behind offside headlamp

[pekingprawn]

Can you add more detail to that? Leak from what system?

[adsgreen]

I dunno - normally I'd agree with vacuum leak but the traction control light is interesting.
perhaps a wheel speed sensor is screwing things up?

Vagcom needed to see the logs - you may also get a generic odb code from a normal odb reader which might help.

How was the car running with the lights on? misfire? rough running? problem idling?

[2manytoys]

MAF Failure

[adsgreen]

But why the traction control light? Thats the bit thats screwy to me.
Are you sure it was the traction control light and not the engine malfunction light?

[2manytoys]

Traction Control relies on the MAF also.

[Jonesy07]

But why the traction control light? Thats the bit thats screwy to me.
Are you sure it was the traction control light and not the engine malfunction light?

yes come up with the traction light.

Fault is showing throttle pedal position sensor/ switch. Got to back to the dealer as not a road side fix.

Nice couple of hours in the rain !

[Jonesy07]

Well its back at Audi for them to look at.

Audi assist just delivered my hire car and its a brand new (30 miles on the clock) A4 170ps Black edition avant !

Was not expecting that so thank you Mr Audi

[stevomepy]

My RS4 did this - - I reckon its one of your engine "brains" - the RS4 B7 has 2 ECU`s - one of mine went kaputt and gave me this same symptom

[pekingprawn]

Keep us posted on the outcome, could be any number of things really.

[thedoluk]

Mine did this today also. Checked the code and it's throttle pedal position sensor. £57 from TPS.

[Shoppinit]

MAF Failure

^^ that is what I would have said. Mine has done this too when the MAFs weren't seated properly. Good to know you found the problem though.

I would be interested to know what the link is with the MAFs and ABS / ESP.

[adsgreen]

I would imagine that it uses the NSF to gauge how much to cut the throttle when the ESP kicks in to limit wheelspin.
More accurate than just measuring throttle position and guessing how much air should be moving.