Not sure what to believe????
Discussion
My recent acquisition of an Audi A6 (V6 TDi) has not been particularly smooth.
The Sunday before last I was cruising out of town to visit some friends when the engine decided to cease producing power. Tickover was fine, just put it into drive and nothing above tickover.
I got the car recovered to the second-hand car dealer I bought it from. They have farmed it out to an Audi specialist (non-dealer). This specialist is now saying the fuel I put in was contaminated and has wrecked the injection system and is going to cost £500 to put right. That is what my translator has said anyway, my Hungarian is not brilliant.
I find it hard to believe that 2/3rds of a tank of diesel to fill up the tank can be perfectly fine for 100km then cause the engine to just lose power immediately. Very difficult to believe that it has wrecked the injection system badly enough to require replacement. Is this possible?
Or, is it more likely that the ECU has packed up and the second-hand car dealer wants me to pay for it????
Any help gratefully appreciated!
The Sunday before last I was cruising out of town to visit some friends when the engine decided to cease producing power. Tickover was fine, just put it into drive and nothing above tickover.
I got the car recovered to the second-hand car dealer I bought it from. They have farmed it out to an Audi specialist (non-dealer). This specialist is now saying the fuel I put in was contaminated and has wrecked the injection system and is going to cost £500 to put right. That is what my translator has said anyway, my Hungarian is not brilliant.
I find it hard to believe that 2/3rds of a tank of diesel to fill up the tank can be perfectly fine for 100km then cause the engine to just lose power immediately. Very difficult to believe that it has wrecked the injection system badly enough to require replacement. Is this possible?
Or, is it more likely that the ECU has packed up and the second-hand car dealer wants me to pay for it????
Any help gratefully appreciated!
A friend recently had problems on his 1.9tdi that sounds similar to yours.
It was the boost control solenoid not working as it should.
Idle was fine, but no power, and almost dangerous to drive because of it.
The variable vane turbos dont use boost pressure to operate, but vacuum instead, so I guess under a fault, engine recieves no assistance from the turbo at all, rendering it very dead and unresponsive.
It was the boost control solenoid not working as it should.
Idle was fine, but no power, and almost dangerous to drive because of it.
The variable vane turbos dont use boost pressure to operate, but vacuum instead, so I guess under a fault, engine recieves no assistance from the turbo at all, rendering it very dead and unresponsive.
Thanks for the responses.
I filled up at a mainstream filling station from one of the big oil companies.
As far as engine power goes it would rev when out of gear to around 2,500 rpm maximum, when in Drive (it's a tiptronic) only idle, no increase at all.
The claim being made is that the fuel has caused a problem with the injection system that requires X, Y and Z to be replaced at a huge cost (exactly what I do not know yet). I find this difficult to believe because for 100 km after fill-up it was perfect, next second no power. If the fuel was damaging something I would expect it to get rougher and rougher until it ceased working, this was instantaneous, fine one second, nothing the next. This indicates to me an electrical/CPU problem rather than fuel.
Likewise if it was fuel blocking injectors or filter a simple clean out should have fixed it. I believe the second-hand car dealer is trying to pass his warranty liability onto me blaming the fuel.
This evening I am going to look at the car, and I am taking the 'family' mechanic with me for advice. I am also asking to see the Audi diagnostics report as well. Visual inspection and a friendly mechanic should get to the bottom of this. I just wish my Hungarian was up to the level required for this technical discussion!
I filled up at a mainstream filling station from one of the big oil companies.
As far as engine power goes it would rev when out of gear to around 2,500 rpm maximum, when in Drive (it's a tiptronic) only idle, no increase at all.
The claim being made is that the fuel has caused a problem with the injection system that requires X, Y and Z to be replaced at a huge cost (exactly what I do not know yet). I find this difficult to believe because for 100 km after fill-up it was perfect, next second no power. If the fuel was damaging something I would expect it to get rougher and rougher until it ceased working, this was instantaneous, fine one second, nothing the next. This indicates to me an electrical/CPU problem rather than fuel.
Likewise if it was fuel blocking injectors or filter a simple clean out should have fixed it. I believe the second-hand car dealer is trying to pass his warranty liability onto me blaming the fuel.
This evening I am going to look at the car, and I am taking the 'family' mechanic with me for advice. I am also asking to see the Audi diagnostics report as well. Visual inspection and a friendly mechanic should get to the bottom of this. I just wish my Hungarian was up to the level required for this technical discussion!
There can be an issue with diesel from badly managed petrol stations - basically if you get unlucky and buy fuel when the station's tank level is getting very low, you can get significant quantities of settled out water that CAN shag (reportedly - only repeating what I read) a diesel injection system.
However, in all logic I'd tend to agree with you that failure due to fuel pollution should be gradual with power loss and rough running before anything drastic happens.
Given the situation, if I were you I'd insist on a main-dealer diagnosis as a second opinion. If they also say that it's fuel quality then it's "your" fault and you'll have to take it on the chin. You could try writing nasty letters to the petrol station concerned but I shouldn't think it'll get you anywhere.
Best of luck.
However, in all logic I'd tend to agree with you that failure due to fuel pollution should be gradual with power loss and rough running before anything drastic happens.
Given the situation, if I were you I'd insist on a main-dealer diagnosis as a second opinion. If they also say that it's fuel quality then it's "your" fault and you'll have to take it on the chin. You could try writing nasty letters to the petrol station concerned but I shouldn't think it'll get you anywhere.
Best of luck.
The car is at an 'independent' VAG Specialist who does not know the sellers. I went down to see the car and talk to the specialist on Friday evening, took our family mechanic with me.
Current situation is the fuel metering unit has failed, possible causes electronic and mechanical.
Mechanical failure means poor fuel, and my cost, electronic means warranty item.
Specialist said he cannot tell the cause until the unit is diagnosed and wanted permission to send it for diagnosis. This diagnosis important because it will also show what needs replacing. Should get the result of this on Wednesday. The fuel has also gone for analysis.
Consensus of opinion is most likely electronic, therefore warranty claim, not the fuel as claimed by the supplying car seller. (Car seller appears to underwrite their own warranties).
Current situation is the fuel metering unit has failed, possible causes electronic and mechanical.
Mechanical failure means poor fuel, and my cost, electronic means warranty item.
Specialist said he cannot tell the cause until the unit is diagnosed and wanted permission to send it for diagnosis. This diagnosis important because it will also show what needs replacing. Should get the result of this on Wednesday. The fuel has also gone for analysis.
Consensus of opinion is most likely electronic, therefore warranty claim, not the fuel as claimed by the supplying car seller. (Car seller appears to underwrite their own warranties).
My 11 year old Pug 405 Tdi ran on petrol once, have run old cars off-road on red from the bottom of a tank full of rusty bits.
Have run diesel with water in it too.
Thats all in older cars, and they have water sensors on the fuel filter.
I'm am quite sure modern Tdi's have a fuel pump tank end, and pump the fuel to the engine end. These pick ups have filters, and then a filter again at the pump end before it goes into the fuel pump itself.
Since water is more dense than the fuel, it sits at the bottom of the filter. If this were to fill right up over a hundred miles or so, then it may cause problems. However, there would be a warning light, and the ecu would likely not let the engine run at all.
It half running suggests something different. Dodgy fuel should be no excuse these days!
Dave
Have run diesel with water in it too.
Thats all in older cars, and they have water sensors on the fuel filter.
I'm am quite sure modern Tdi's have a fuel pump tank end, and pump the fuel to the engine end. These pick ups have filters, and then a filter again at the pump end before it goes into the fuel pump itself.
Since water is more dense than the fuel, it sits at the bottom of the filter. If this were to fill right up over a hundred miles or so, then it may cause problems. However, there would be a warning light, and the ecu would likely not let the engine run at all.
It half running suggests something different. Dodgy fuel should be no excuse these days!
Dave
when you mean the metering unit,do you mean the airflow meter.These are re-known to play up in all vw and Audi cars.You can use the same parts from the Skoda range to replace these and are cheaper that way.According to my mate,who runs a garage.Audi/VW are looking into doing 'exchange' units for these,as new ones are up to £300.If these fail,you are right in saying they go into a 'safe' mode.
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