VAG diesel tech help required please!

[Cavcraft]

1994 Audi 1.9TDi: discovered today it's not starting due to what I can only describe as a rotor arm on the plunger on the top of the diesel pump, underneath the top cover of said pump. We noticed this rotor arm affair has what looks like brushes which track across a route on the top of the pump. These brushes look like the things fitted to the bottom if a Scalextric car if anyone's familiar with these pumps.

 

Basically we need to remove the rotor arm to replace or repair the bushes but can't work out how to get it off. Does anyone know how to remove this arm please as we can't figure out how to?

Thanks in advance!

[Cavcraft]

[Lacquer Peel]

What makes you think that's the reason it's not starting?

According to a tiny diagram I found it's a solenoid controlling injected fuel volume, are they known to fail?

[Cavcraft]

It's because when we held a screwdriver down on the bush thing the car would start, but as soon as it was released it refused to go. There seems to be a soldered track that the 'rotor arm' runs round and as the bush/es are knack'd it won't make contact.

[dieselnutjob]

Have a look at this document

http://www.christiantena.net/motor/vag/ ... ik-eng.pdf

 

most of the sensors on these engines have a "substitution function" which means that if a sensor fails the ECU will make a best guess and try its best to carry on.

 

The arm thing is the "Modulating Piston Movement Sender". This doesn't have a substitution function and when it fails the engine dies.

 

I would have thought that suitable error codes would appear in the ECU to verify this.

 

Soory but I don't know how to remove it

[dieselnutjob]

it does say in that doc that it is non contact and uses magnetism

[Cavcraft]

Many thanks, DNJ, that's a brilliant link and shows the bits we need. I've just mailed a mate who runs a VAG specialist and included that link, hopefully he'll know how to remove it.

Someone on RR thinks the pumps aren't really 'strippable' but I can't get my head round not being able to buy bits like this to get the damned thing running. Worse case scenario I'll have to try a second hand pump instead. Would you happen to know if 100/105/110/130 pumps are the same at all?

 

Many thanks once again.

[dieselnutjob]

the 110 pumps are similar but have a different cam plate to inject more fuel, but I suspect that it will work

the 115/130 etc are pumpe duse so a totally different technology

the best place to get info about these is forums.tdiclub.com

[Lacquer Peel]

The pump (Bosch VP37) is used on lots of cars, not just VAG SHIT, you'd be better off consulting a diesel specialist.

[Cavcraft]

Cheers. Found an A4 in a scrappy today and whilst the pump looks pretty much the same the banjo bolt fitting at the top (two pipes off it, one goes to fuel filter) is slightly different being on the side not the top and the immobilisor wire is shorter.

I'll get on that TDiforum later, thanks.

[dieselnutjob]

I think you want older stuff like mk3 Golf / mk4 Passat 1995 to 1997 or so