I have an 02 jetta wagon that I have replaced 4 crank shaft sensors and the ignition coil. I get the car back and it will run good for 2 wks and then again the same problem, this last time it let me set and it would not start and i had it towed to the dealer,they could not find anything wrong although they only tried to start it a day later and it started,no codes.it turns over but doesnt start,seems flooded.I also replaced the fuel filter!
Ouch. Intermittent problems in a computerized circuit are the worst.
Does if fail while driving, or just occasionally fail to start?
It sounds like you are fairly certain that the problem is lack of spark. If you or the dealer has carefully checked every connection and ground in the ignition and there are no stored codes to give you clues, you might consider a junk yard ignition computer. That is a very expensive experiment, and not very scientific, but compared to $100 an hour for dealer diagnostic time, it might be a reasonable next move.
You need to find a shop with a good diagnostician, not someone who will just throw parts at the problem with your time and money. I can’t imagine that all of those crank sensors are going bad—unless there’s a good reason, such as being installed improperly, getting saturated with oil, etc. Unless you have a warranty or some other tie to the dealer, consider an independent shop used to working on VWs. I don’t own a VW, but being as there is the internet, there have to be about 1,000 VW boards out there that can possibly offer you advice, as well as perhaps recommending a knowledgeable shop in your vicinity.
And as Manolito said, intermittent problems are really the pits.
the car just occasionally fails to start! sometimes it will start an 1hr-2hrs later even a day later!