Engine speed sensor (G28) 2.5tdi 163

[VagCabby]

Hello, fitted a new battery 2 days ago as mine was completely dead, I've never had any issues with the car apart from hard starting(new battery seems to have fixed this) anyway ever since fitting the battery I have had the engine management light flick up and the glow plug light flashing when first starting the car(this doesn't happen every time) code I have got from VCDS is my engine mount valves not working which I'm not botherd about but I'm getting

Engine speed sensor (G28) no signal

Car runs fine once I clear the codes and only returns occasionally when starting the car from cold. It runs rough before clearing the code and goes into limp mode. I believe this is the crank position sensor, could someone point me into the right direction as to where this sensor is! Searched high and low and can find no info on it.

 

[b16 will]

Your onto the right sensor anyway.
Location is unknown. Have you googled it ?
You want to hope it's not like the 2.0 tdi where its behind the flywheel with an off centre Allen bolt...

 

[VagCabby]

Yup googled it and people say its a pain to get to but no one states where it is! Haha. Did find one site which said on the right hand bank behind the oil filler but I can't see any sensors there. Its got to be bottom side of the engine I'd hope. I had the flywheel off about 3 months ago and don't recall seeing a sensor behind it

 

[b16 will]

They somtimes pick up on the rear main seal. I know myself that the v6 tdi is quite crammed in...well, mine is !!

 

[JasonS]

I replaced mine a while ago, although I later found that it was water ingress to my ECU connector.

The G28 connects via the grey plug on the firewall behind the engine, follow the cable from this.
It's very hard to get to the sensor, you can reach it from the offside wheel well. I'll see if I have any photos of when I changed mine.

 

[VagCabby]

Your a star! Thankyou. I shall look this weekend and also check my ECU. It does seem like a loose connection or something shorting out due to it not showing up all the time

 

[adamss24]

Crak sensor is on passenger side bell housing- it's held in place by a 10mm bolt. You might want to do it from underneath with the engine cold as the exhaust downpipe is in the way...

 

[VagCabby]

Cheers mate, thanks for preventing me from burning my arms!

 

[VagCabby]

Update!

The sensor was indeed on the left side of the gearbox and ran up to the grey plug at the back of the engine bay. A few pain the the **** cable ties to cut off but got there in the end.

Old sensor out and it looked like it was worn down and also covered in dirt...I did have a failed DMF 3 months ago which I had replaced, would this have caused wear on the sensor? New sensor in and the engine feels so much more responsive! Its pulling like a train, so happy! Have to see if the engine management light comes back or not.

 

[Ovid]

Cant see how dmf could rub on sensor unless it came loose

 

[VagCabby]

After checking it over and cleaning all the crud off it, it wasnt scoring, the small metal tip had 3 curved notches on it which looked like damage but they are just part of the design.