Intermittant loss of power...55 plate, 2.0 TDi, Auto Tip

[ally0000]

Hi

In September 08 I bought a Ex fleet, 55 plate A4 Avant, 2.0 TDi with the tiptronic auto box. It has 90k on the clock and a full Audi history. It's great and so far we just potter about the city (Edinburgh) to and from the shops and work. Sometimes (once or twice a month) we go for a longer run for maybe an hour or so, but it's never driven even close to hard as we bought it after our daughter was born so she's in the back.

A couple of times now there has been a major loss of power. The car still goes OK so we are not stranded but you hit the gas and nothing happens. Both times I turned the car off and on and the problem went away.

Last night was the second time it happened so this morning I put it into manual mode and gave it a bit of a revving on the way to work, not too much as it was rush hour and icy but still revved it higher than usual, it was a bit smokey out the back for a while but that stopped.

What I'm thinking (hoping) is that because we jsut drive it really conservatively there is some build up of 'stuff' and when this reaches a point the loss of power issue appears.

I am reluctant to give it to Edinburgh Audi when the fault is not there as intermittant faults are obviously notoriously difficult to diagnose when they are not happening. I'm wondering if anyone has had a similar problem or can offer any advice.

Thanks,

Ally

[Alan02]

Hi, It could be a few things,such as a turbo sensor,or wiring fault or an EGR fault but whatever it is,the ECU will store the fault so the dealer shouldn`t have too much problem in sorting the fault.If you explain the fault and it isn`t on at the time,they can road test the car with the computer connected to read the data.

[ally0000]

Thanks for the reply, that's good to know that it stores the fault. I should just get it booked in, last thing I need is it breaking down when my wife is driving it.

[Audi_man]

Hi.. I have 05 2.0 Tdi, Auto and have the exact same problem as you. It happened to me once aboout 3 weeks ago, but twice today...

If you find a solution let me know...

[ally0000]

The car is booked in for this Thursday to have the engine manangement logs checked. Cost for that is £58 and if there is a repair after that, then that cost will be waived.

Will post an update when I know more

Cheers,

[size12]

Did it just lose power or did the dash light up? no light usualy = no fault code!
sounds more like it just needed a good blow out, leave the missus and daugter at home and go play

[ally0000]

There were no dash warning lights, I told the guy at Audi this and he seemed to think there may still be logs.

[ian vincent]

I had the same problem on my B7 Avant 2.0 TDi - intermittent loss of power accompanied by lots of smoke out the exhaust.

Over the course of about a week (when I was on the road and away from my normal dealer) the intermittent turned into a full time condition that turned out to be a turbocharger issue - I don't know the full details as it was a company car at the time and they just fixed it and sent the bill to the leasing company.

Rgds Ian Vincent

[Teflon]

Here's a tip - there are half a dozen possible causes, all but one of which should show up on a fault scan (as recommended in the previous posts). The most common fault is a duff MAF sensor, which shows no error codes. Mr Audi will stick you for about £100-150 to replace it, DIY is nearer £40.

Word of warning - an Audi dealership might tell you that you need a new turbo and they are going to need £1300-2000 of your hard-earned to do the job. The most common turbo "problem" of sticking VNT vanes can be cured for peanuts, so don't dive in and let them strap on a new turbo without coming back to the forum for further advice.

I hope this helps, Teflon.

[ally0000]

Hi,

Thanks for the responses, very useful. Audi actually called today to say that they probably won't find anything when they hook up my car for the diagnostic test as the fault was probably lost when it was turned off, but they'll still charge for it.

I'll post an update tomorrow.