E46 M3 Home Maintenance

[mat205125]

Just a quick note to let everyone know that today I am bathing in the warm glow of self satisfaction that is gained from managing to find a fault, and eliminate it, without any cost of main dealer or indy labour.

My mood yesterday morning wasn't so great, however, as my car started with a ugly sounding vibration that could only be attributed to a missing cylinder. The normal "worst case scenario cold sweat panic" washed over me.

Luckily I had the day off, so a moments thought targetted investigating the spark as a first action. Without going through the process of fault finding, I was able to diagnose a faulty coil pack on number 1 cylinder within 30 minutes of the bonnet being lifted, and an inspection of the plugs also uncovered that they were well past their best ("fked" is more like it!) - the latter had allegedly been changed by a main dealer (according to the service invoice) less than 20k before when the car was owned by someone nearer Southampton. They clearly hadn't been! Either take your car to a dealer you can trust, or ask to see the parts replaced before they are binned - thankfully that was the only stamp from that dealer in the book.

With the car out of action, it was on with the shorts and skid lid to ride the road bike to buy a replacement set of plugs and a new coil pack. With my wallet a bit lighter (they ain't shy on the price of the plugs!), I then rode home to refit and reassemble .... Thankfully the weather was lovely, so the 25 mile round trip was actually a pleasure, and I'd planned to get out on my bike on my day off anyway.

Everything reassembled, running and finished in little more than an hour of spanner time. Plugs made a load of difference, as the car is noticably smoother running.

Moral of the short story ... For many jobs, there is no need to be scared of the M badge. It's funamentally just metal and wires like your first A-Series mini was .... just a bit more in the way of wires, and less receptive to swearing and hammers like the mini was

Get your spanners out!!!

[oli_quick]

Excellent well done...for numpties out there (myself included)

http://www.m3forum.net/m3forum/showthread.php?t=14...

[Neil.D]

These E46/E39 (maybe a manual E92) are probably the final M cars that can be worked on without a computer. |
As you say, they all share basic fundamentals and have consumable parts.
A ramp sure makes things easier but Im willing to give most sensors and common problems a go in my garage.

[Targarama]

Luckily it was coil pack no 1 and not no 5 or 6, otherwise it would have taken you a bit longer

Plugs can get tired in nearly 20k miles...

[mat205125]

Targarama said:

Luckily it was coil pack no 1 and not no 5 or 6, otherwise it would have taken you a bit longer

Not at all. All the coil packs need to be removed to change the spark plugs, and (as the picture link above illustrates) the entire top of the engine is exposed to work on once the cabin filter assembly and strut brace are removed.

For this job, the car is actually very easy to work on, and reach. Certainly easier than any transverse V6 that I have worked on, for example.

Edited by mat205125 on Tuesday 2nd February 14:25

[Targarama]

mat205125 said:

Targarama said:

Luckily it was coil pack no 1 and not no 5 or 6, otherwise it would have taken you a bit longer

Not at all. All the coil packs need to be removed to change the spark plugs, and (as the picture link above illustrates) the entire top of the engine is exposed to work on once the cabin filter assembly and strut brace are removed.

For this job, the car is actually very easy to work on, and reach. Certainly easier than any transverse V6 that I have worked on, for example.

Edited by mat205125 on Tuesday 2nd February 14:25

I was joking!

I know all about BMW straight six coil packs. I had pack 5 go on my Z4 3.0L. Only showed under load, so I had 5 journies before I found the culprit.

[mat205125]

jz325i said:

Just out of interest, what make was the duff coil pack?

My car is running the ERA coil packs, rather than the Bosch ones. I had no idea that there were two options, so bought both from the dealer and returned the unused option once I'd finish re-assembly - Thankfully this was a journey in the car rather than another 25 miles on the bike

I'm not sure if there are a preferred manufacturer on the various forums, however I can testify that my car still runs 4 original coil packs that it left the factory with in 2002, with the new one I fitted (date coded as manufactured during 2008), and one date coded in 2005 - God I sound like a train spotter, checking such things as DOM codes on coil packs

[darreni]

I changed all mine to be safe.
The Bosch ones are £16 ish from german & swedish.