PDA

View Full Version : Fuel Pump Problems


jusmurph
12-01-2007, 09:33 PM
I'm having a few issues with my A6 2.5 Tdi, which nobody seems to be able to fix. The auto box is going into 'Limp Mode' because of a fuel pump problem, and a code read indicates that the high pressure pump is faulty. The pump has been replaced £****! but its still showing the same fault. A injection pump specialist has looked at the car, connecting the full bosch kit directly into the fuel pump, but it still sugests changing the pump!
So now audi and a specialist have run out of ideas-I'm open to any advice.
(The replacement pump was new not an exchange item):(
mastertech
13-01-2007, 12:36 AM
Can,t quite see why the gearbox would go into limp mode for a fuel pump fault?? from memory the only signal the gearbox uses is a load signal from the air mass meter although they may share some CAN BUS imformation(pump has its own ECU biult in and talks to main ECU via CAN
the pump is very reliable--and if fails ,fails totally! What are the fault codes???has a wiring check between ECU,s been done--open/short curciuts etc Are you sure its the injection pump and not the electric lift pump in the tank???
jusmurph
13-01-2007, 12:50 AM
Tha Bosch code reader gives (57)-Ignition timing fault, and says that it has caused the limp mode. Everone who's looked at it, seemed to think it was the pump.
jusmurph
13-01-2007, 12:51 AM
Sorry- air mass meter was one of the first things Audi changed.
mastertech
13-01-2007, 01:09 AM
Sorry don,t work with bosch fault codes -only AUDI codes.
is timing OK ,valve /belt timing and commencement of injection timing that is checked via basic settings on diagnosis tester (VAG COM---VAS5051 etc)
auiron
13-01-2007, 02:02 AM
Hi jusmurph, I did have a fuel pump replaced about 3 years ago. It was rebuilt by a company in Canterbury, Kent. When it started failing and right up until it was working very poorly, the car did not go into limp mode. Could be a loose earth.

Is this the only Auto Gearbox problem you have had, "limp home mode".

This link does discuss this limp mode problem, - not an Audi though - and is better than nothing: http://autorepair.about.com/library/a/1h/bl843h.htm