2001 BMW 330 BMW E46 Poor to Start and Run

ALASTAIRB25

MEMBER
2001 BMW 330
6 CYL
2WD
MANUAL
119,000 MILES

Hi

I have a BMW E46 330Ci 2001. It has recently had an inspection II, A crank position sensor and a new battery.

After the service it ran great, huge difference in responsiveness! A few weeks later it struggles to start and runs rough when first ticking over. It feels rather lethargic compared to just after it was serviced.

I took it in and there are no error codes logged. Sometimes it takes 5 seconds + cranking to start.

From what Ive read this could be various problems. Coil packs, Vanos failure or the other cam position sensors.

Seeing as the spark plugs where replaced on the service is there a chance a coil pack can be damaged during this, it seems most likely by my reasoning, and the fact Bremi seem to be a rubbish company for such items, seems a well known German car problem!

Is there an easy way to diagnose each, I dont suppose you can use a multimeter to test a coil pack, did wonder if that would be dangerous! The garage I took it too seem a bit stumped because there are no codes to read, I was hoping they would do more than just say the computer says its all alright boss, sadly not :-(

I just dont want to get into replacing a load of bits and the problem not be solved

Kind Regards
Alastair

1 Reply

DOCHAGERTY

MECHANIC
9,601 POSTS

It is possible the coils are faulty, replace the coils if they are a solid black color. If they have a gray collar, they are replacement coils and should be OK. Reset all adaptations and drive it for a few days. Part # 12-13-1-712-219 for the Bosch coils, they seem to be the flavor of the month. If OE coils, they will be dated with week and year of manufacture. I would also consider replacement of the plugs, use part#12-12-0-141-871 and eliminate the possibility of a bad plug.