Sudden Shut off in 2006 jetta TID

[TDICHICK]

I have a 2006 Jetta TDI which has an intermittent reoccuring problem with random shut off while either stopped or in the process of downshifting. The clutch as been replaced, as well as the fuel filter (four times), and various other sensors. This is an intermittent problem which, up until a few weeks ago, only happened in the summer when the AC was on.
Though under warranty when this was reported, the car is now out of warranty and they are still 'unable to duplicat the problem' There have been numerous technicians working on this car, and nobody seems to be able to figure out the issues with it.

Any and all advice would be much appreciated!

[chittychittybangbang]

Is it the one with the square headlights or round headlights? They still sold the mk4 Jetta in 2006 in Canada but not the US but I don't think they had it in TDI so I'm assuming you have a US spec mk5 Jetta with the round headlights.

Is it manual or DSG? I assume manual even though DSG also have clutches.

Go to autozone or the like and get an error code scan. Also see if past service receipts have any notes or codes written on them. I don't have a clue what it could be since that's very weird.

My best guess is that the in tank electric fuel pump is intermittent. When stopped or downshifting, the fuel pump at the engine is no longer enough to keep fuel flowing and the engine shuts off. At other times the electric fuel pump in the fuel tank is enough to keep it running. This is a total guess based on your statement on the fuel filter, it's probably because the techs think it's fuel related due to the numerous fuel filter changes. This doesn't explain the AC thing though. It could be a bad ground or ECU.

[farmboy98922]

My jetta is doing the same thing. It has got so bad that I can't drive it. It is in the shop now. I had it at a dealer in Bellevue but it was not doing it all the time and they could not figure it out. I now have it at a indenpendent shop. i will post the results in the next coulple of days.Mine is a auto transmission It would never die but just drop to a idle by the time i would get stopped it would start running fine. this went on for about a month until it got to bad to drive. I have 102000.0 miles on it.

[Gruppe d]

That sounds like a bad flywheel. The two halves of the flywheel are loose, common problem on older DSG.

Originally Posted by farmboy98922

My jetta is doing the same thing. It has got so bad that I can't drive it. It is in the shop now. I had it at a dealer in Bellevue but it was not doing it all the time and they could not figure it out. I now have it at a indenpendent shop. i will post the results in the next coulple of days.Mine is a auto transmission It would never die but just drop to a idle by the time i would get stopped it would start running fine. this went on for about a month until it got to bad to drive. I have 102000.0 miles on it.

[TDICHICK]

This one is a manual with the round lights. There are no error codes listed and the car has done the shut off once fully hooked to a computer set up to read the codes, nothing happened.
I'm working with my own tech from VW (as this has gotten that far) but he doesn't even have a clue. He's finally admitted that he doesn't think it is the fuel filter getting clogged, so in another month he'll get the car again and see if he can find another solution. I don't think he'll manage to get it fixed. The car as under 50,000 miles on it!
The grounds on the car have been checked and cleaned twice. Our tech even took apart the clutch and did the grounds they wouldn't normally be able to reach.
I'm just out of ideas, and I think they are too!

Originally Posted by chittychittybangbang

Is it the one with the square headlights or round headlights? They still sold the mk4 Jetta in 2006 in Canada but not the US but I don't think they had it in TDI so I'm assuming you have a US spec mk5 Jetta with the round headlights.

Is it manual or DSG? I assume manual even though DSG also have clutches.

Go to autozone or the like and get an error code scan. Also see if past service receipts have any notes or codes written on them. I don't have a clue what it could be since that's very weird.

My best guess is that the in tank electric fuel pump is intermittent. When stopped or downshifting, the fuel pump at the engine is no longer enough to keep fuel flowing and the engine shuts off. At other times the electric fuel pump in the fuel tank is enough to keep it running. This is a total guess based on your statement on the fuel filter, it's probably because the techs think it's fuel related due to the numerous fuel filter changes. This doesn't explain the AC thing though. It could be a bad ground or ECU.

[TDICHICK]

That doesn't really sound like the same issue. My car literally turns OFF. As in, I have to re start it in moving traffic or when I'm at a stop sign or a stop light. I have to turn the key to the car off position and turn it back on. There is no trouble with the start, but the car has literally turned off! Good luck with your car!

Originally Posted by farmboy98922

My jetta is doing the same thing. It has got so bad that I can't drive it. It is in the shop now. I had it at a dealer in Bellevue but it was not doing it all the time and they could not figure it out. I now have it at a indenpendent shop. i will post the results in the next coulple of days.Mine is a auto transmission It would never die but just drop to a idle by the time i would get stopped it would start running fine. this went on for about a month until it got to bad to drive. I have 102000.0 miles on it.

[chittychittybangbang]

Have they checked the fuel pressure while it was stalling? A car needs air, fuel, and compression to run. Compression isn't the problem because that would be obvious and they should have checked that.

The only place air could get shut off is at the intake manifold - there's an electrically actuated valve. Fuel could be getting clogged at the fuel tank. Did they try removing the fuel pump at the fuel tank and checking for clogging? Did they try replacing the fuel pump at the fuel tank? It's possible the ECU is bad and is preventing fueling under certain conditions.

While I don't think it's the cause, it's possible the timing belt is somehow off and causing poor camshaft timing. Look through the timing belt article and check the index marks. If they're close it's not the problem.

[TDICHICK]

I know they checked the fuel pressure, idle speeds, and that they've run the fuel system to check for clogs. The problem is that this is so intermittent it has only done it once for them and about 20 times for me and my family while driving it. The timing belt was indeed checked and was found not to be the problem.
I will however double check each of these with my tech when the car is in next. Thank you!

Originally Posted by chittychittybangbang

Have they checked the fuel pressure while it was stalling? A car needs air, fuel, and compression to run. Compression isn't the problem because that would be obvious and they should have checked that.

The only place air could get shut off is at the intake manifold - there's an electrically actuated valve. Fuel could be getting clogged at the fuel tank. Did they try removing the fuel pump at the fuel tank and checking for clogging? Did they try replacing the fuel pump at the fuel tank? It's possible the ECU is bad and is preventing fueling under certain conditions.

While I don't think it's the cause, it's possible the timing belt is somehow off and causing poor camshaft timing. Look through the timing belt article and check the index marks. If they're close it's not the problem.

[Robotek]

Chitty, do the PD have a fuel shut off solenoid or something that would act like that?

[chittychittybangbang]

Originally Posted by Robotek

Chitty, do the PD have a fuel shut off solenoid or something that would act like that?

Not that I am aware of. So far my best guess is that fuel is cutting out. The question is why. My guess is that it's either a physical fuel delivery problem or an electrical bug which doesn't like to show up.

tdichick, does it otherwise idle smoothly? If you remove the level sensor electrical plug on the outside of the coolant reservoir, is it dry or is it wet with pink coolant? It should be dry.