So I have a 2000 TDI that I've gone through since it was a basketcase (unknowingly) when I bought it. New clutch/fw/pp, got a VAGCOM to sort out IQ and timing, etc.
Anyway, the car has been puffing a little white smoke on -cold- starts (ie. after work or overnight), vibrating slightly during idle with AC on, vibrating heavily / catching itself during idle with AC off, blowing black smoke during hard accel, idle would hang higher for a second or two coming to a stop, and the exhaust smelled strongly.
At first I suspected it was the head starting to go since my car is a 'timing event' car with a 'new head' but as I read around and thought about it I figured that there was a more likely situation - the injector nozzles were old and dripping/bad spray pattern since all of the symptoms fit and I am pretty sure they are stock (201k).
Anyway, I bought a real Ross-Tech KII cable since my 3rd party cable sucked - ended up arriving today. I was playing with the cable and decided to check IQ on a hunch - I noticed that IQ was dead on around 4 with the AC on but when I turned it off the IQ dropped to 2-2.5 and the bad idle set in.
Well... hmm, if I bump the IQ up to be like 4 with the AC off... Yep. IQ with AC off is now 4-ish and AC on sits around 5. Dead smooth idle. Drove it around today and the engine is FAR quieter, turbo spools earlier, no more vibration at all, little to no smoke during acceleration, and zero smoke on cold start. Exhaust doesn't smell nearly as bad either.
I'm curious to see how much better the car is MPG wise. When I bought the car it was doing 34-ish, recently I have been doing 41, and now hopefully I will see 42 or 43.
Anyway, just thought I'd throw some observations out there for people with similar issues.
Anyway, the car has been puffing a little white smoke on -cold- starts (ie. after work or overnight), vibrating slightly during idle with AC on, vibrating heavily / catching itself during idle with AC off, blowing black smoke during hard accel, idle would hang higher for a second or two coming to a stop, and the exhaust smelled strongly.
At first I suspected it was the head starting to go since my car is a 'timing event' car with a 'new head' but as I read around and thought about it I figured that there was a more likely situation - the injector nozzles were old and dripping/bad spray pattern since all of the symptoms fit and I am pretty sure they are stock (201k).
Anyway, I bought a real Ross-Tech KII cable since my 3rd party cable sucked - ended up arriving today. I was playing with the cable and decided to check IQ on a hunch - I noticed that IQ was dead on around 4 with the AC on but when I turned it off the IQ dropped to 2-2.5 and the bad idle set in.
Well... hmm, if I bump the IQ up to be like 4 with the AC off... Yep. IQ with AC off is now 4-ish and AC on sits around 5. Dead smooth idle. Drove it around today and the engine is FAR quieter, turbo spools earlier, no more vibration at all, little to no smoke during acceleration, and zero smoke on cold start. Exhaust doesn't smell nearly as bad either.
I'm curious to see how much better the car is MPG wise. When I bought the car it was doing 34-ish, recently I have been doing 41, and now hopefully I will see 42 or 43.
Anyway, just thought I'd throw some observations out there for people with similar issues.
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