Maintence/Questions about 2003 VW Jetta

[kunoman1]

Hey all, I have a few questions about my powertrain on my 2003 MK4 Jetta I lovingly call Arthritic Heidi.

1. When I start it cold, the tachometer will bounce from ~700 -> 1300 on idle (particularly while cold and in drive or reverse - park seems to have a more stable idle). Anyone have any ideas what could cause this and whether it is dangerous for the vehicle. The engine warning light has come on a few times as a result of this but turns itself off after ~5km. Sometimes as a result of this, the car will shake for a minute or two.

2. When the automatic transmission shifts gears, it gives a small lurch similar to the feeling of a newer driver driving manual. What could be causing this? If it helps with a vague diagnosis, the tiptronic system is slow and pretty unresponsive.

Would a VAG scanner tell me what is wrong if there are no engine lights on?

Thanks all! Just trying to fix a few issues before lending the car to my sister while I'm off working in China.

[Impreza]

For the idle problem I would suggest cleaning the throttle body first.

[kross9]

might be all the hotdog buns you try to defrost in the engine bay killed it...

Try cleaning the PCV valve, it sometimes get gunky in there.

Check your tranny fluid it might be tarnished. you may need a tranny.. as MG1 or icedady about those.

[Traum]

Just to confirm it for perspective, this is a MkIV car with the 2.slow engine, right?

[kunoman1]

Originally Posted by kross9

might be all the hotdog buns you try to defrost in the engine bay killed it...

Try cleaning the PCV valve, it sometimes get gunky in there.

Check your tranny fluid it might be tarnished. you may need a tranny.. as MG1 or icedady about those.

LOL the hot dog buns, forgot about that

Kk i'll give'r a look and oh god a new tranny...

Originally Posted by Traum

Just to confirm it for perspective, this is a MkIV car with the 2.slow engine, right?

It's the 1.8T

[StanleyR]

could be vac leaks causing the idle bounce.

IMHO, turbo cars of that age tend to be problematic as they age. Esp VW's

[kunoman1]

Thanks for all the tips guys! I didn't really have a chance to get it all checked out/clean the sensor so I'm hardparking it in a driveway and covering it. I'll sort it all out when I return from Asia