Starting problems with 2004 Z4, 3.0I

[Fastatv]

So I fired up the Zed, drive down the road about half a mile for some beers. I get out of the car, grab some brews, get back in the car, turn key...nothing, not even a click. After about six or eight tries, it cranks, and starts. I'm like ****, now I can get home. Pull her in the basement, turn her off, again, would not start. Methodology:
- Charged battery at a 2 amp rate, charged to 100% in about 15 minutes, so, probably
not the issue
- Not a fuse of any kind because on the first failure at the store, nothing...then cranked
and started, so I felt no reason to check.
- Next thing that went thru my mind was the key. Since I wasn't getting even a "click" I
thought the key might be the culprit, It was very dirty and I thought it was not being
recognized by the ignition switch, so gently cleaned it up with electrical contact cleaner
and tooth brush.....and I was excited, tried it, big no go.,,,,DAMN....LOL
- Now time to get into voltage drops, I connect my volt/ohm meter up to the "battery
jumper posts under the hood.
- Key off, door open, static voltage was 12.6 vdc, interior lights on,
- Next reading, door open, key switched to the "run" position, 12.4 vdc,
- Ok, so far, so good, now I move the key to the start position, 12.2 vdc, not
much of a drop, only .2 vdc.
- I try this again, switch to start position, with lights on, no dimming of the head lights
what so ever
- Seemed to me the starter was not getting any voltage any of significance.
- So I pondered a bit, then I had a friend get in the car and try to "crank" it while I tapped
on the starter. Cranked and started, and did this three times.
Starter was faulty, but it was a bit different than I had experienced before, very little voltage drop and no clicking, and no dimming of the lights.
Purchased a new starter from an Auto Box Store, about one hour, maybe a little less to remove and install, works like a dream. Hope this proves useful to someone. Rick

[toolmanchris]

Had a similar issue with a 4WD (not BMW) a couple of years ago. Turned out to be the solenoid contacts in the starter that had burned away.
Fortunately they were available for £15 off ebay.
Dismantled the starter, fitted them and bingo working fine. I dont know if these are available for the BM starter but it wasnt a difficult fix and could potentially safe quite a few quid

Chris