zslnk
Veteran Member
Hello,
2003 ALH Jetta 5 speed - 280k-km
Background:
I bought this car from an older lady that didn't do much other than drive it around town, original owner. The intake was clogged and head ports were clogged. I did a through cleaning and walnut blasted the head on the car, it's spotless now. Car is stock, EGR working. Turbo has no play, new actuator is set correctly and has lots of power, uses no oil and runs perfectly.
Problem:
On a cold start, the car fires one/more cylinder instantly (even at -25c) but it feels like they cylinders don't all start at once. You have to keep the starter engaged a little longer than I'm used to make sure they all catch or else it will die. Once running, the RPM's are around 1100 and it runs a bit rough and smokes (smelly diesel cloud, excess fuel) for a few seconds then settles down to 900RPM and the smoke clears up.
Starter is new, battery is known good (load tested) from my BEW.
Injection pump timing is right on the target line
IQ starts around 15mg/str then trends down smoothly to around 3mg/str
Fuel, air and water temps are within 1deg.c at startup
Fuel filter is new and the car has been diesel purged x2
Injector balance starts within spec and then settles to almost even numbers (COLD -0.66,0.02,0.14,0.49) (WARM -0.16,-0.02,-0.24,0.42)
No air is present in the clear fuel line
Glow plugs are good, draw uniform current (individually checked with amp-probe)
This AM I started the car, logged some data then shut down. 30min later (coolant temp still <0c), I restarted and it still had an easy, but uneven initial idle for about 5sec.
The car had oil in the intercooler but nothing in the intake to indicate a runaway, just dry carbon buildup.
The car runs smooth with lots of power and gets great mileage (4.7l/100k on snow tires and winter fuel)
Compression or leaking down injectors? My primary TDI is a BEW and it starts uniformly and generally seems more 'refined' during a cold start. When warm the car starts instantly and smoothly.
2003 ALH Jetta 5 speed - 280k-km
Background:
I bought this car from an older lady that didn't do much other than drive it around town, original owner. The intake was clogged and head ports were clogged. I did a through cleaning and walnut blasted the head on the car, it's spotless now. Car is stock, EGR working. Turbo has no play, new actuator is set correctly and has lots of power, uses no oil and runs perfectly.
Problem:
On a cold start, the car fires one/more cylinder instantly (even at -25c) but it feels like they cylinders don't all start at once. You have to keep the starter engaged a little longer than I'm used to make sure they all catch or else it will die. Once running, the RPM's are around 1100 and it runs a bit rough and smokes (smelly diesel cloud, excess fuel) for a few seconds then settles down to 900RPM and the smoke clears up.
Starter is new, battery is known good (load tested) from my BEW.
Injection pump timing is right on the target line
IQ starts around 15mg/str then trends down smoothly to around 3mg/str
Fuel, air and water temps are within 1deg.c at startup
Fuel filter is new and the car has been diesel purged x2
Injector balance starts within spec and then settles to almost even numbers (COLD -0.66,0.02,0.14,0.49) (WARM -0.16,-0.02,-0.24,0.42)
No air is present in the clear fuel line
Glow plugs are good, draw uniform current (individually checked with amp-probe)
This AM I started the car, logged some data then shut down. 30min later (coolant temp still <0c), I restarted and it still had an easy, but uneven initial idle for about 5sec.
The car had oil in the intercooler but nothing in the intake to indicate a runaway, just dry carbon buildup.
The car runs smooth with lots of power and gets great mileage (4.7l/100k on snow tires and winter fuel)
Compression or leaking down injectors? My primary TDI is a BEW and it starts uniformly and generally seems more 'refined' during a cold start. When warm the car starts instantly and smoothly.
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