A4 multitronic hesitation

[Audifan25]

Hi,

Can anyone help with my multitronic gearbox problem, car is a 2004 2.4 sport and had the gearbox ECU replaced last September under an extended warranty when all the PNRDS lights were staying on.
The car has now developed within the last couple of weeks an intermittent fault where when I engage drive,or reverse, there is a significant delay of 2 - 5 seconds before the gearbox engages and on 2 occasions when it does engage there is an audible "bang".
Also intermittently if I attempt hill start (not a steep hill) with the box in drive I need to keep my foot on the brake to stop the vehicle rolling backwards.
Audi dealer have plugged car into their diagnostics and it shows the gearbox ECU has probably gone again and they will cover this under their 2 year parts guarantee. However first they want to drain the fluid and check the wiring and the valve body (hydraulic control unit) to see if it is those.
Has anyone come across this before, to me if the fault codes show ECU then that has gone ??
Would the hydraulic control unit show up as a fault on the cars computer

[danclyon]

Hi,

Can anyone help with my multitronic gearbox problem, car is a 2004 2.4 sport and had the gearbox ECU replaced last September under an extended warranty when all the PNRDS lights were staying on.
The car has now developed within the last couple of weeks an intermittent fault where when I engage drive,or reverse, there is a significant delay of 2 - 5 seconds before the gearbox engages and on 2 occasions when it does engage there is an audible "bang".
Also intermittently if I attempt hill start (not a steep hill) with the box in drive I need to keep my foot on the brake to stop the vehicle rolling backwards.
Audi dealer have plugged car into their diagnostics and it shows the gearbox ECU has probably gone again and they will cover this under their 2 year parts guarantee. However first they want to drain the fluid and check the wiring and the valve body (hydraulic control unit) to see if it is those.
Has anyone come across this before, to me if the fault codes show ECU then that has gone ??
Would the hydraulic control unit show up as a fault on the cars computer

OK so that's not the ECU that's the hydraulic control unit. Others here will doubtless tell you tales of woe and I'll be doing the same I'm afraid.

We had the same thing - hesitation to engage gear, rolling back. The dealer replaced the hydraulic control valve and fluid (fluid 3 times I might add) which gave us 6 months of "odd stuff" happening - including the gearbox deciding to have a go-slow pulling onto a roundabout which nearly placed me in-front of a 40 tonne lorry....

End result - complete new gearbox. All seems well now.

If they are saying they want to replace the fluid - let them. They replaced it when they did your ECU (as the ECU is buried in it) so suggest they pick up the tab for that!

Cheers,
Dan.

[Audifan25]

Thanks Dan,

Dealer had car in yesterday and have concluded that the ECU has gone but cannot gurantee that when they replace it that something else has'nt also failed. They say that they looked at the hydraulic control unit but cannot test it without removing and sending to the factory.
2 week wait now for the new ECU to be put together to the cars chassis number.

[danclyon]

Thanks Dan,

Dealer had car in yesterday and have concluded that the ECU has gone but cannot gurantee that when they replace it that something else has'nt also failed. They say that they looked at the hydraulic control unit but cannot test it without removing and sending to the factory.
2 week wait now for the new ECU to be put together to the cars chassis number.

Good luck - hope it's just the ECU.....

I'm already thinking about getting rid of mine in the next year owing to all the problems with the multitronic!