1999 Jetta TDI Engine problems

6 months ago, on a foggy morning (60 deg F), My Jetta TDI would not deliver any signicant power such that the car would only go 10 MPH. I had to have the car towed to the dealership. They replaced the injector pump under warrantee.

Then, just this week, on a foggy morning with similar temperature (just coincidence?), the exact same thing happened. This time I was 75 miles from home, so I had the car towed to the nearesr dealer. There, it sat for 2 days before they even looked at it (arrrrg). When they did try to drive it, they saw nothing of the intense power loss that I experienced. They said that "nothing is wrong now".

One thing I noticed though, is that in both cases the car would take alot of cranks to finally start in the days preceeding the main power loss.

When I pick up the car, I plan to question them with regards to:
- Condition of EGR Valve, MAF sensor,
- Status of chip settings
- Cleanliness of the cooer and intake manifold

Anybody have any similar experiences?

check antishudder valve, in tdifaq

109 Relay?

look for N75, and antishudder valve. It wouldn't be the relay 109 as the car still starts and runs. Also check your maf, and never go back to the dealer. Find a knowledgeable member in your area (What's up with members from 14,000+ not putting where they're from? Are they scared we might get them?), and check your car out.

Sorry about my rant. /images/graemlins/grin.gif

Assuming it's not the changeover valve, could it be the fuel pickup?

Or perhaps a moisture issue with one of your electrical connectors?

IIRC, there is a spray for these connectors that displaces moisture. I used to use it on distributor caps on gassers after cleaning the engine. Might be a good idea to keep a can in the trunk for the next foggy morning. Spray connectors one at a time until the problem is solved. Don't forget the ECU connector.

My suspicion areas would be MAF connector, ECU connector, and fuel pump connector. Also check the N75 connector.

Is this a New Jetta or the old A3 body syle?

I would have to agree with what others have said about moisture intrusion into an electrical connector.

[ QUOTE ]
- Status of chip settings

[/ QUOTE ]
Is the ECU chipped? If so, and especially if it was done recently I'd check the ECU connector.

Good thing you didn't have to pay for that pump! /images/graemlins/wink.gif

Did you get any response from the throttle? Would the engine rev without trying to drive it?