So after many years of never having a problem, suddenly my '99 1.8T 5 speed Passat is starting to shit the bed.
For months now I have been tracking down a vac leak that is causing a CEL and throwing a code of 17544 - LTFT Add. Fuel Bank 1 too lean blah, blah, blah...
To this date I still haven't figured it out even through I've replaced every bit of rubber that has anything to do with vacume or fuel.
As a side note, when I try and do a test of block 071, the fuel tank leak test, it aborts right as it begines the leak down part of the test. The leak detection pump goes through all of it's bumping and whining noises and then nothing. It just says, "Test Aborted." Why?
But now I have something else that is even more frustrating. When under WOT the car now bucks and shudders. And usually only in third gear when the boost really starts to rise. I have checked to see that the ICM is in fine working order. And it is. So I'm think that this problem is a fuel related issue and not spark related, because the bucking only happens when I really stick my foot into it. Just runnning around town at about half throttle produces no problems. It's only when I go to full throttle that it shudders. And of coarse this causes a Flashing CEL. Not good.
The code is in two parts:
#1) 16684 - Random/Multiple Cyl. Misfire Detected - Intermittant
#2) 16686 - Cyl. 2 Misfire Detected - Intermittant
Also, I have checked the spark plug in cyl. # 2 and it seem fine. I just replaced them about 2 or 3 months ago. Their coloration looks normal.
This all leads me back to a fuel injector not working properly. I looked around the base of the injectors where they fit into the manifold and suprisingly there is no leaking coming from around any of them. That never was an issue with this engine like it has been with other 1.8Ts.
So, how can I test the fuel injector to see if it is within specs? And what are the specs I should be looking for? I did a search this morning to see if I could find anything in the forums, but no luck.
The bucking is getting very bad now and the car isn't very reliable at this point and I need it to be.