I have recently bought a 1999 Passat TDI (110bhp), when I let it run up through the gears 2nd accelerates smoothly all the way up to 4000 rpm, but
3rd hits a dead spot just over 3000 and another just under 4000. Anyone have any ideas?????regards Craig
craig schrieb:
VTG-Problems? Leaking Pressure-hose? Problem persistent or intermittent? If you shift to third with rpms as low as possible and rev third all the way up - any dead spots then?
Ingo
Sounds like the MAF. Try disconnecting it and driving around -- if the behaviour changes, then i'd suggest replacing it.
The Bosch MAFs (Mass Airflow Sensors) have been a weakness on the VW TDI engines.
Lots of great into @
where is the MAS and will it affect anything else ?
craig schrieb:
V(ariable)T(urbine)G(eometrie) - there's a moving air deflector inside the turbo assembly - if it is jammed the turbo will produce less boost, very rpm dependent, often intermittent.
Ingo
Just took the old girl for a thrash and she seams to be okay now, I've only had her two months and never really let her stretch her legs before perhaps she was owned by a little old lady ????
Diesels get dirty very quick. If you drive gently there will be a build-up of soot inside the engine and in the exhaust. So every once in a while drive a short stretch at a higher rpm and she'll be ok. My old A2 Golf diesel had a soot value of 2.3 last year (K-value, used to measure the amount of visisble soot in the exhaust during MOT's here in the Netherlands). A K-value of 3 is allowable for a turbo diesel engine and 2.5 for a normally aspirated engine. They measure this 3 times in a row while trashing the engine to the max rpm for 3 seconds without load (so make sure your cam belt is in good shape..). So last year it was 2.3. I was driving only on roads where 80 km/h is allowed. Now I drive mostly on motorways at speeds of 100-120 km/h. the last MOT gave a K-value of 0.77 and a acceleration time of 0.9 seconds (from idle to max rpm).
Drive the diesel for a mile or so at max rpm in 2nd or 3rd gear and she'll open up nicely...
Remco
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