I had this problem for a few weeks... got a tune up... and the mechanic told me I had partial misfiring of one of my cylinders...after the tuneup he told me that one of my coil packs was completely dead. It ran like crap... chugging along on the road. I got them replaced as per my recall by the dealership. The car was running fine.

The dealership told me they scanned the car after the coilpacks were replaced... and I still have the following codes

SAE / VAG
P0411 / 16795 Secondary air system: throughput faulty
P0420 / 16804 Bank 1, catalytic converter system: not effective enough
P0422 / 16806 Bank 1, main catalytic conveter: not effective enough
P0441 / 16825 tank ventilation system: throughput faulty

so I don't have another appointment for a week and a half (not many dealerships in the area)...
my car is still just stalling/shutting down on it's own at idle (ie at stop lights). Also... when that occurs or if my car has been parked for a long time... it is difficult to start (the engine still cranks). It eventually starts.

Also.. the engine just cuts out at times... the rpms drop... and the power is off.... this occurs while I'm driving... it's like the car has ran out of gas or something? The CEL comes on.. and the oil icon shows up on the center display

The catlytic converter I can get replaced under warrenty (130000km/8years) ... but I am past the regular warrenty (100000km/5years) so I will have to pay for other things.

I don't suspect any electrical/battery issues ... it seems to be possibly related to this tank ventilation issue??? I don't know?

What could be the problem? how can I get it corrected... and most important... how much will this cost?

Any advice/help is appreciated

 

Did all this surface after the tune up?

 

The problem still continues after the tune up... as well as after the coil packs were changed.

 

Try searching all the forums for the four codes:
16795
16804
16806
16825

These aren't codes we see very frequently, so maybe you'll get some ideas by looking through other forums as well. This is something I would probably leave to the dealer to sort out, rather than an independent mechanic. I'd do a little searching right now, but I'm sleeeepy. :-/

 

thanks... i've been searching for days already... i'll wait til i see the dealership i guess