car only doing 130 miles on full tank

[kd]

Hi there,

Just wondering if anyone has had this before, my car broke down and was taken to my local Audi by AA as it just stopped dead in its tracks like its out of fuel. Audi said it was the fuel pump and a few minor associated bits and after a whopping £700 got the car back. Once I got it back the car only seems to do about 130 miles on a full tank. I thought maybe it was just the first fill up but just filled up again and on half tank its on 80 miles. I took it back just now to Audi and they said they dont know what it could be and said to bring it in when it hits reserve so they can see for themselves (I dont think they believed me). I know its not much to go on and me not being mechanically minded am not sure if in the process of replacing a fuel pump if any settings need to change or something they may have missed. The car runs a bit jerky like its getting too much fuel (i think) but no other apparent smell of fuel.

Another issue I had which was unrelated was that the coolant was leaking and I had to keep filling it up every few days (what I thought was the pipes directly off the filler tank) as they looked corroded slightly. They said they fixed that (I will get the specifics off the invoice) and the following day the coolant tank was empty. I filled it up a few times over the weekend and took it back to Audi who did a check and said this time it was the secondary water pump which due to the work involved was £1000 inc labour. They saw my shocked face and said they would knock it down to £700 as I had just had the coolant fixed, this just seems so expensive and very coincidental or maybe something they did wrong in the initial work?? weird thing is for the last few days the water has remained topped up in the tank so not had to fill up and I am just wondering if its the water cap that a few people mentioned on the forum...I cant see it fixing itself??

Anyway sorry for the long post and any thoughts would be so helpful. I dont have complete faith in this dealership but as they initially was taken there not sure if I should now take it somewhere else to have it rechecked? I need to go through my old receipts and I am sure MRC replaced the fuel pump a couple of services ago too.

Thanks

KD

[davs4]

After run pumps can leak like a sieve but is an easyish job to do your self for not a lot of outlay. Dual temp sender can make fuel economy vary if it's faulty. Water cap cheap and easy fix and if they didn't top system up fully could be the reason.

[kd]

Hey thanks for your comments, I will look into that. With the mileage I was zero'ing the trip computer and using that reading for what its doing on a full tank. Is that the same as what you were saying?

[searider]

When the after run pump went on my S4 it dumped a litre of coolant. RAC turned up and couldnt find leak but once topped up there was no leak - I guess it only leaks when under pressure. Drove the car 60 miles gently on the motorway to my mech with no water leak and had pump changed then. So, after run pump leaks can be strange. £700 is way too much to change the pump.

Which Audi dealer do we need to avoid?

[kd]

Thanks for that info. I am just going today to pick up a replacement cap. Today was the first day after a few that the warning light kicked in and the water was just below minimum. I hope that the cap will fix it if not I will take it local to a friend who has a garage.
It was John Barclay Audi in Wandsworth. Its just a service centre that I believe now also services Bentleys. I did actually have good experience with them previously but this time was just way overpriced for everything and just have a gut instinct that things were done that didn't require to me, but of course not knowing much about the mechanics I can't really base that on any proper knowledge

Will keep you posted if the £7 cooler cap does the magic

[jimbo1234567]

afterrun pump takes 2 hours ish to change, you just have to pop the inlet manifold off. looks like they are trying to pull yer pants down.

[davs4]

I'll change it for you cost you a bacon sarnie though....

[lynchy]

When the after run pump went on my S4 it dumped a litre of coolant. RAC turned up and couldnt find leak but once topped up there was no leak - I guess it only leaks when under pressure. Drove the car 60 miles gently on the motorway to my mech with no water leak and had pump changed then. So, after run pump leaks can be strange. £700 is way too much to change the pump.

Which Audi dealer do we need to avoid?

All of them

[kd]

I'll change it for you cost you a bacon sarnie though....

how about a ploughmans??

I changed the coolant cap and so far so good but I think after a few days I will know more, last time it took a couple days.. as for the fuel this is another full tank I did, from full to the red light it did 121 miles!! on the computer the MPG looked normal, when I filled up the tank it estimated the car would do 260 miles I think and I tallied it up with the actual car mileage and it was exactly 121 miles...

[davs4]

Ploughmans works for me When did you change the temp sender last as that threw my fuel out?

[jimbo1234567]

think you need 2 new lambda s in there to sort the fuelling out

[kd]

Right so in the last 4 days after I changed the coolant tank cap it has not dropped the water level and doing pretty well... how the hell did they diagnose it to be the secondary water pump??

I had all those sensors replaced about 2 years ago at MRC.

I have been keeping check and the car is taking in full 55 litres and the trip computer shows 130 miles completed which tallies up with the actual mileage of the car. Pardon my ignorance on this but if it is actually using all that petrol and the tank is actually empty with those miles showing on both readings would it still be a sensor??

This is the third tank now at normal town driving too...

[Contigo]

http://www.rs246.com/index.php?name=PNp ... ic&t=78434

[Blue_Thunder]

Have you checked around the fuel filter to check you haven't got a fuel leak caused by corrosion? Now these cars are reaching a certain vintage, i've read quite a few posts where this has happened.

[ShaneyB]

Is it actually running out of fuel or showing in the red and then you're filling up? I had a scenario in my old B5 S4 like that so I got a couple of fuel cans filled with Optimax (old school) and drove the car until it physically ran out of fuel. Low and behold it had another 70 miles in it although the needle was below the read and the DIS said zero miles.

I was wonering if it could be the sender unit in the tank giving an innacurate read?