Turbo weirdness
 

Hey Drivers,

New to this forum, but have read a lot of the threads. Lot's of good information! I'm hoping for some help...

My turbo ('01 Jetta TDI) died on me a few months ago (about 120K miles, so not too upset). Dealer puts a new one in - all good, right.

Over the last month, very intermittently, I get the following weirdness. Start engine, begin to pull out, and there's no boost (I have a gauge). I can hear the turbo working and it feels like there's a little boost (maybe 60% typical), but nothing on the gauge. Then the Check Engine light goes on. After parking it and letting it sit for a few hours or overnight, everything will operate normally, although sometimes I will still get the light, even though the turbo's working.

This is VERY intermittent - maybe 6 - 10 times over the last month and a half. It seems like it might be temperature related, because it's cold where I live. But it's nothing as simple as warm - it works, cold - it doesn't. It also either is happening on the start or not - it never develops as I am driving.

Took it back to the dealer, who couldn't get the problem to re-occur, but based on the Check Engine code, told me I either need a new O2 sensor or a whole new micro-processor. Not going there, yet!!! Talked to my regular mechanic, who said the dealer's a crook - there's not even an O2 sensor on this model. He thinks it might be a little vacuum leak, or a loose electrical connection or something, but he also has to have the problem happening to check it out. Since then, it's only happened twice, neither times during business hours.

Anybody have any experience or knowledge about this??? Anybody...

P.S. The tag comes from when I get a little aggro with my driving - my wife grabs the dash, rolls her eyes and says "Jetta Drivers!"

RE: Turbo weirdness
 

sounds to melike a vaccuum problem, probably have a bost leak somewhere. check your piping and DV (if applicable) and see if there are any leaks in the hoses or cracks in anything in the piping. other than that, (which im 99% sure it will be) you can check to see if the diverter valve is hung, if so, it could always just be letting the exhaust go thru, which is highly unlikely with the negative vaccuum of the valve. so, check your piping. If not piping, check hoses, as you just had a new turbo put on, it will more than likely be a connector loose or a small unnoticed crack. lemme know how it turns out.

;)

RE: Turbo weirdness
 

Thanks boots, good suggestions.

Here's another little clue - maybe it will reveal the answer. Today's really cold. Upon starting, got the check engine light, and no boost. On a hunch that it might be related to a temperature sensor problem, after it was warmed up, I turned it off, restarted it and got boost! Still had the check engine light, but now the turbo works?!!?? Any thoughts???

RE: Turbo weirdness
 

well, thats kind of screwy in and of itsself, i mean, the turbo will make boost regardless of sensor, i mean, it has exhaust being pushed through it, so i am sure it would make boost at that point.... i will have to go outside nd remove a few fuses and see if i can recreate the problem in my driveway on my 1.8t. i still am leaning towards vaccum, but i think thats a bit screwy. lemme have a day or so, im doing some interesting stuff on my cars this weekend, so we will see = D

RE: Turbo weirdness
 

See myReply to Post(01-09-07) on Bad Turboon 2004 Jetta TDI, I am sure your problem was the same as mine! Bad wire harness with 2 shorting wires! Mine was blowing some white smoke and sem to be acting eractic also. Dealer fixed for free!

RE: Turbo weirdness
 

Thanks toledotom!

I read your post about your TDI. Nice to hear you have a good dealer - not so sure about mine. Anyway, I'll have that wire harness checked out. Cheers,