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Cursed Audi A4

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My friend’s 2006 Audi A4 2.0 started dying on her a few months back. She replaced the battery to no avail. She then took it to a shop and they seemingly fixed it. It died again. She took it to the Audi dealership. They charged her $1200 to fix something to do with the temperature/vacuum system. A few days after it was out of the dealership and supposedly fixed, it started dying again.

She has taken it back to Audi a few more times. They have replaced the knock sensor, the cam shaft, the fuel pump, and the fuel filter, all for another $1300 (they are supposedly not charging her labor).

We are stumped. Audi is stumped. The national Audi guys are stumped (yes, they called them in). My friend doesn’t know what to do. She is essentially paying the Audi dealership for them to experiment on her car. Anyone have any suggestions?

You’re going to have to give us lots more details about it ‘dying’. What happens? When? Where? After how much driving? Everything about it.

The dealer is throwing parts at it and charging ur friend. They suspect no fuel pressure so they change fuel pump. If they test old fuel pump and it’s fine, why did ur friend pay for a new one? Labor is “Free”, put old pump back in. They need to use a data capture logger and see what car is doing AS is dies. No ignition signal? No fuel pressure? Audi techs are smart. They sure charge enough for their expertise?

Texases - initially the car shut off while idling or stopped at stop lights. Over time, the car would sputter and jerk while moving and eventually would shut off while accelerating. At this point, there doesn’t seem to be much of a pattern.

Stoveguyy - the techs at Audi spent weeks trying to replicate the problem. It was only after they replaced the cam shaft that it finally died on them as well. They tested the fuel pressure in the engine at the point and said it was low. That led them to replace the fuel pump and filter. They then tested the engine again and said the fuel pressure was much better and the car was running “great.” My friend went to pick the car up yesterday and paid them for the second round of repairs. She only got less than a mile from the Audi service department before the car sputtered and jerked again. She turned around and dropped it back off.

Here’s something to check. When it does this, loosen the gas cap, see if it helps. If it does, then there’s something wrong with the evaporative control system, a vacuum’s being created in the gas tank making it hard for the pump to work correctly.

Hey runonsandwich,
Wow! That is a lot of parts to throw at a car all under the assumption that it will fix the problem… I honestly thought Audi techs knew how to diagnose problems better than that :(. A lot of the things you mentioned being replaced makes very little sence to me… A cam shaft… realy? What are the odds that the cam shaft would be at fault? very little i assure you. My suggestion: take it to a different Audi shop, see if there is a mom and pop shop that deals with german vehicles. You never know what an old wrencher might find out for you. Beyond that it seems the current shop has been “testing” and correcting issues relating to the fuel system. The question I have is did they ever test the ignition system? The charging system is another possibility but due to the fact you said the car is sputtering before stalling perhaps the ignition system is more likely. Without a sufficient spark to ignite your fuel/air mixture your friend could very likely expierience the very same problems you describe.

Hope your freind is able to once and for all defeat the curse, Best wishes

Has the fuel pressure at the rail been tested? Usually if the fuel pressure there is off, it isn’t the fuel pump or fuel filter, it is the fuel pressure regulator. This gadgets sets the fuel pressure at the input to the injectors and is modulated by engine vacuum and an assortment of other things depending upon the car, like intake air temperature, coolant temperature, and altitute (barometric temperature). These things fails, usually in the form of a vacuum leak. If it failed, the symtom you report could occur. Also, if any of the other inputs failed, the same symptom could occur.

Usually a dealership would have all the tools and knowledge to diagnose this. They’d hook it up to their computer analyzer and could monitor all the ignition components, the O2 sensors,the knock sensor, the crank sensor & other timing events, in real time. They can take a “snapshot” and see exactly what is occuring. That, combined with reading the diagnostic trouble codes would usually pinpoint the cause. Has your shop done all that?

There’s not enough info known to be able to narrow down what the cause of this problem is but I’ll play devil’s advocate for a minute.

It’s very easy to think that a car problem can easily be sorted out when that is often not the case at all.
Cars often develop problems with no codes present and every test under the sun being performed by the most competent of mechanics leading nowhere. Not everything is in black and white.

If the public wants more clearcut black and white automotive clarity then the public is going to have to demand that cars be taken back to contact point distributors, non-EEC controlled carburetors, and the total elimination of all computers, modules, and assorted interconnected bells and whistles.

This is only going to get worse in the future; no ifs, ands, or buts about it and that’s just a mechanical fact of life unfortunately.

runonsandwich, I had a chevy silverado a few years ago with a bad catalyitic combustor. The symptoms were very similar to what you have described, especially when accelerating.