Cosmic Green
Veteran Member
Hi Everyone!
My 99.5 Jetta, a real high-miler (665,000km/412,000mi) developed a problem this past winter:
After driving during a snowfall for approx. 45 minutes, the engine would begin to cut out intermittently, especially at light throttle (okay, I know there isn't a throttle, but you know what I mean).
It would get progressiviely worse, and eventually the MIL would come on, sometimes even flashing. Codes generated were all over the map; nothing conclusive there.
Letting it dry out for a day would cure the problem. It certainly seemed that water was getting into electrical connections somewhere.
This spring, it also began to do the same in rainy weather, and this past Friday it died totally after driving through a large puddle.
After the indignity of a tow home, I removed the battery, battery tray, airbox, and wiring duct cover.
Here's what I found:
Five wires had worn through their insulation to various degrees, exposing the copper within. All were in the same place: The 3" long harness guide on top of the starter. This is a logical place for this to happen, as the engine assembly, and hence this harness guide, is constantly vibrating, but the harness itself is solidly attatched to the body less than a foot away.
The damaged wires were for the coolant temp. sensor, injector lift sensor, one of the inj. pump wires, and glow plug supply. I'm amazed the thing ran like this for as long as it did!
I highly recommend that anyone with with more than 500,000km/300,000mi. take the time and perform an inspection here. Once you get it out of the guide, you'll have to unwrap the tape from around the harness, give it a very thorough cleaning (I used spray contact cleaner) and give it a good once-over in good light. I found most of the damaged wires quickly, but two were found later as the insulation had just worn through. All damage was within a 3" span.
I spliced in new two-foot lenghts of wire to replace the damaged sections. The car started right away, and I drove it in heavy rain yesterday and in a heavy, wet snowfall today (mother nature's spring surprise) and it ran great.
I hope this helps.
Cosmic Green
My 99.5 Jetta, a real high-miler (665,000km/412,000mi) developed a problem this past winter:
After driving during a snowfall for approx. 45 minutes, the engine would begin to cut out intermittently, especially at light throttle (okay, I know there isn't a throttle, but you know what I mean).
It would get progressiviely worse, and eventually the MIL would come on, sometimes even flashing. Codes generated were all over the map; nothing conclusive there.
Letting it dry out for a day would cure the problem. It certainly seemed that water was getting into electrical connections somewhere.
This spring, it also began to do the same in rainy weather, and this past Friday it died totally after driving through a large puddle.
After the indignity of a tow home, I removed the battery, battery tray, airbox, and wiring duct cover.
Here's what I found:
Five wires had worn through their insulation to various degrees, exposing the copper within. All were in the same place: The 3" long harness guide on top of the starter. This is a logical place for this to happen, as the engine assembly, and hence this harness guide, is constantly vibrating, but the harness itself is solidly attatched to the body less than a foot away.
The damaged wires were for the coolant temp. sensor, injector lift sensor, one of the inj. pump wires, and glow plug supply. I'm amazed the thing ran like this for as long as it did!
I highly recommend that anyone with with more than 500,000km/300,000mi. take the time and perform an inspection here. Once you get it out of the guide, you'll have to unwrap the tape from around the harness, give it a very thorough cleaning (I used spray contact cleaner) and give it a good once-over in good light. I found most of the damaged wires quickly, but two were found later as the insulation had just worn through. All damage was within a 3" span.
I spliced in new two-foot lenghts of wire to replace the damaged sections. The car started right away, and I drove it in heavy rain yesterday and in a heavy, wet snowfall today (mother nature's spring surprise) and it ran great.
I hope this helps.
Cosmic Green
