Serious Intermittant Problem with ABS|tc|rev counter|and gearbox

**c4burona** · 15-06-2008,01:49 PM

i have just recently bought an a6 se on a 99 with the 2.4 triptronic gearbox, when the car seems to be cold or driven at slow speeds everything is good, but when it decides to go into a bad mood the car's ABS light comes on the t/c is turned off the rev counter stops working and the gearbox goes into safe mode leaving you stuck in 4th gear and it also flashes up with an oil pressure problem!! it all either works or it doesn't so it must all boil down to the same problem, i thought it could of been the crank sensor causing the rev counter not work leaving all the above not working but this has been changed and still no difference, does any body have any idea's because the missus is chewing my ear off about the damn thing!!
many thanks
john

**Crasher** · 15-06-2008,02:06 PM

Have you had a fault code read carried out on the engine, trans and ABS systems?

**lonky** · 19-06-2008,11:51 PM

have you checked the plenum chamber for water ingress ?

Been known to cause plenty of electrical faults when the relay box gets soaked

**snugglebum** · 20-06-2008,06:05 PM

Hi i also have the same problem with my a6 2.4 multitronic......just started today. Must be a common problem ? Anyone have any ideas ?
Many Thanks
Lee

**snugglebum** · 20-06-2008,06:14 PM

Sorry to sound like a newbie guys buts where is the plenum chamber and how do i check it ?
Many thanks
Lee

**snugglebum** · 20-06-2008,08:17 PM

hi guys i found it......its the battrey bay

**snugglebum** · 20-06-2008,08:18 PM

2 post till email

**snugglebum** · 20-06-2008,08:59 PM

i can email now

**snugglebum** · 21-06-2008,01:28 PM

Hi Guys
Good news Ive just had my A6 in my m8s garage. Hes put it on the computer and the fault code is 0727 (Engine Speed Input Circuit No Signal ). The speed sensor is located on the top of the gearbox he says. He called a local supplier and a replacement sensor are around £15 + VAT. Ive had the sensor ordered so hopefully it will be fitted early this week.

The bad news !!! 1 of the mechanics that works at my m8 garage has come accross this problem b4 on another AUDI A6 multitronic. The car had the same simptoms and he diagnosed the same fault. The sensor was changed but it didnt fix the problem. It turnd out the gearbox ECU was knackard. He scrapped the car

Ill let you know if changing the sensor fixes the problem (fingers crossed)

If it turns out to be the gearbox ECU, any ideas on cost of replacement ? or if its a DIY job ?

Hope this helps
Cheers
Lee