Distributer Cap

[KenC]

Does anybody have a picture of what the underside of a GOOD distributer cap should look like? I think mine might be toasted. (I have pictures of it, but I can't upload them to my webspace because I lost the software to do it). The underside of mine is REALLY dirty and the carbon post in the middle is pretty damn short.

I also checked for a spark on each of my plugs and I was getting weak spark on some and no spark on others... does this mean that my cap needs to be replaced?

[Spaz]

ken catch me on aim.

[Bill 84 318i]

I had the same kind of not-start backfiring deal as you (though only in wet weather) for awhile.

Tune up (cap/rotor/plugs/plug wires) and it went away for good. They're cheap as hell man, just do it.

[KenC]

I just got a new cap and rotor in the mail from good ole BMA, and all I can say is HOLY SHIT! My cap and rotor (especially the latter) were absolutely wasted. The little metal blade that comes off of the rotor was completely gone on my old one. I surprised that they were even able to produce a current!

[Bill 84 318i]

Routine maintenance > all.

[arnoldgtr]

I just noticed that the cap is much cheaper from World Parts suppliers like Importec. Is your cap a Bosch made in Spain?
After driving an M3 for 5 years, the price of a 318i cap and rotor is downright cheap. The Evo M3 cap and rotor are about $150.

[KenC]

Yeah, the cap is a Bosch from Spain. It was ~$16 shipped for the cap and rotor from BMA.

[Axxe]

Routine maintenance > all.

[golde30]

Yeah, the cap is a Bosch from Spain. It was ~$16 shipped for the cap and rotor from BMA.

hot damn, i checked BMA for cap and rotor for an m20, and its like ~$65 shipped... how the hell is it that much more for the m20? weak sauce.

[arnoldgtr]

No comparison. The M10 cap looks like it belongs on a VW. The Motronic M20 cap is much heavier.
Lifespan is another factor. In my experience, the M10 cap is only good for 30-40K miles, while the M20 cap will go over 100K.

[Axxe]

Right now I'm replacing the factory original rotor, distributor and wires. 160,000 kms on it. Not too shabby, if you ask me, although the contacts are almost completely gone. When wet it misfires like a mofo for 30 seconds after start.