Misfire/really bad idle

[ATPDK]

Hej!


I started up my 2003 Z4 3.0i after the winter from a few days ago - went fine.

Today I would try again, but immediatly it went into a really bad idle (cold start).
It misfires a lot, so it sounds like an old fishermans boat. It jumps approx 4-500 RPMS up and down by itself.
And farts a lot from the exhaust.

Car is ALWAYS stored in minimum 8 degrees C garage.

How often does this engine needs new sparkplugs?
Can it be “the compression problem”?

HELP

[1000rr]

Sounds like a dodgy coil pack.

[Ducklakeview]

Spark plugs about 60k, pointless guessing, it need a diagnostic scan. Could well be ca coil pack or two, but just replacing things gets expensive. Post your location and see if any members nearby can help.

Mike

[ATPDK]

I'm pretty sure it is spark plugs or coils.

Can I safely drive the car to nearest BMW dealer, if it runs only on 4 or 5 cylinders?
The "Check engine" lamp is "only" yellow.

It is really hard to find qualified persons who know anything about this in Denmark - it is a pretty rare car and engine.

[ph001]

Driving it with unburned fuel going past the lambda sensors and cat does them no good at all. You don’t need a specialist to understand or replace coil packs, pretty much every modern petrol engined car in the world has them!