2nd fuel pump failed

[b-ill]

Hi, i am new to the forum, a friend of mine introduced me to it after he owned a few D2's.

I have a 2002 S8. LPG'd (Prins)

Brief history on the car, i bought it from my neighbour, who owned it from new!! I paid the bargain price of £600, it had various issues but most of them fixed them selves. After running it for a month the fuel pump failed.

One evening it began to chug on the driveway the fuel was very low, i managed to flick it onto LPG and drive it to fill it up with fuel. I left it running whilst fuelling, when i finally switched it off it wouldn't start again, sometimes it would run on a few cylinders then die.

I purchased a Siemens replacement pump from eBay, my local Audi specialist removed the fuel assembly and confirmed the old pump had failed. He then swapped the pumps over by taking the assembly apart. A few days later he got his "assistant" to refit the assembly into the tank.

At the time of first starting it after refitting the car had a quarter of a tank, the car started and ran for 10 or so minutes then began to chug, we then put around 20 litres of fuel and it ran fine.

Over the next three weeks I kept the car at around half a tank (FUEL) but mainly using LPG as you have to start it on fuel and let it get to temperature before it will run on LPG. When occasionally running it on fuel i noticed it would start to chug and splutter between half and quarter of a tank, i also noticed a slight whining noise from the boot when inside the car, this would only be heard when idling.

Then one day it decided to chug really badly at around half a tank, so i filled it right up. On the way back from filling it right up it died completely, i couldn't get it back onto LPG in time to get me home. I had to get a friend to tow me off the M40.

The next day i thought i'd do the basics like check the fuse, the fuse had blown, i replaced the fuse with another 25amp fuse and still no joy. I then measured voltage across the fuse box terminals, i had 13.8V on the crank of the key. So the relay is doing its job.

I have had the same Audi guy round to take the pump out again, he has bench tested it today and informed me that the pump has seized!!

I've spoken to the seller on Ebay that I purchased the pump from, they've told me I need to return the pump to them and they will send it back to Siemens to be tested. If faulty they will replace it or refund. This could take upto a month. To get things moving i've ordered another pump.


My main concern is that this is going to happen again? Something must have caused the fuel pump to seize and blow the fuse. Should I change the fuel filter? Has the "assistant" incorrectly fitted the assembly back into the pump ?

Any thoughts of the above would be massively appreciated as i am awaiting the arrival of the 2nd pump and if theres anything that could be done to prevent it happening again i'd like to do it beforehand.

Thanks

Billy

[mannyo]

The Audi guy has done something wrong when refitting the new pump. The fuel delivery mechanism on the D2 is quiet complex, and to refit the fuel pump properly requires a great deal of skill to get it working correctly.

The tank has two parts, and the fuel pump as well as pumping fuel to the engine also needs to get the petrol from the other half of the tank. The first symptoms you describe RE: chugging at low fuel level are indicative that the pump was not refitted correctly and could not properly pump fuel from the passenger side of the tank to the engine. The result could be the pump running dry and thus eventually seizing up because it overheated.

This youtube video shows how to install the pump and how complex it is to do it blind.
https://www.youtube.com/watch?v=no5K...A&spfreload=10