Brett San Diego
Veteran Member
I'm just sharing my experience with a no-start issue that happened (kind of) all of a sudden with my TDI. Car is a 2002 Jetta wagon with manual transmission with 232,000 miles. I acquired it just 11,000 miles ago. I have no service history on it. I say "kind of all of a sudden" because about a month before it simply would no longer start at all, it began giving an occasional hard start. The first hard start happened after the first time I left the car outside in the "cold" (San Diego) night. May have been coincidental... But, I didn't pay much attention since most times it would start up instantly as usual. For a month or so, it continued to give an occasional hard start requiring several seconds of cranking (sometimes multiple times), but it always started up and ran fine afterward. It never stalled while running.
Finally one morning, it would not start at all. I cracked injector fuel lines and cranked, and there was no fuel delivery. Following very helpful posts here, I ruled out the fuel shut-off solenoid and replaced the fuel filter and thermostatic T O-ring with no change. I was able to prime the filter just fine with a mityvac, but I found I could not pull fuel through the pump. It just sucked air and wouldn't hold vacuum. At that time, I became convinced that the injection pump seals were the problem. I purchased the seal kit from Dieselgeek and watched the youtube videos (search "TDI pumpseal," and look for the video broken into seven parts). Finally, this past weekend, I got a chance to do the seal swap. All went really smoothly. With the new seals (top and bottom quantity adjuster gaskets and pump head O-ring), the system would hold a vacuum when pulling through the disconnected injector fuel return line as shown in the videos, and fuel was slowly pulled into the pump. After the priming, the car started instantly. I also picked up a Ross-Tech VCDS so I could finish the job. Injection quantity (IQ) was initially a little low at around 2. Slight "hammer" adjustment and I torqued the quantity adjuster down at 3.4. The car is completely back to normal and starts instantly.
None of the gaskets were visibly damaged, but I think the problem was the pump head O-ring. It was completely intact when I removed it, but it was hardened and flattened, and I presume it just didn't have the pliability to fill the gap anymore. Shrinkage from the colder weather may have contributed to the seal failure.
I should mention that my pump wasn't leaking, at least not seriously. There may have been a little seepage, but fuel wasn't pouring out of it. Nevertheless, the problem was the seals, and after a month of down time, I'm very happy to be back commuting in the TDI rather than the Range Rover at 14 mpg.
Brett
Finally one morning, it would not start at all. I cracked injector fuel lines and cranked, and there was no fuel delivery. Following very helpful posts here, I ruled out the fuel shut-off solenoid and replaced the fuel filter and thermostatic T O-ring with no change. I was able to prime the filter just fine with a mityvac, but I found I could not pull fuel through the pump. It just sucked air and wouldn't hold vacuum. At that time, I became convinced that the injection pump seals were the problem. I purchased the seal kit from Dieselgeek and watched the youtube videos (search "TDI pumpseal," and look for the video broken into seven parts). Finally, this past weekend, I got a chance to do the seal swap. All went really smoothly. With the new seals (top and bottom quantity adjuster gaskets and pump head O-ring), the system would hold a vacuum when pulling through the disconnected injector fuel return line as shown in the videos, and fuel was slowly pulled into the pump. After the priming, the car started instantly. I also picked up a Ross-Tech VCDS so I could finish the job. Injection quantity (IQ) was initially a little low at around 2. Slight "hammer" adjustment and I torqued the quantity adjuster down at 3.4. The car is completely back to normal and starts instantly.
None of the gaskets were visibly damaged, but I think the problem was the pump head O-ring. It was completely intact when I removed it, but it was hardened and flattened, and I presume it just didn't have the pliability to fill the gap anymore. Shrinkage from the colder weather may have contributed to the seal failure.
I should mention that my pump wasn't leaking, at least not seriously. There may have been a little seepage, but fuel wasn't pouring out of it. Nevertheless, the problem was the seals, and after a month of down time, I'm very happy to be back commuting in the TDI rather than the Range Rover at 14 mpg.
Brett
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