Super wierd starter issue.*cough* jlevie *cough*

[Kozworth]

89 e34 m20b25

My mom called me up saying she heard a clunk and thought she ran over something, then seconds later the car died and she coasted into a parking lot. Not really sure what the clunk was, but found the negative terminal split in two so I replaced it.

However, she tried starting the car afterwards (after it died). It sounded like it was just the starter spinning and not poking out. I hit it a few times, no cigar, so figured I had a worn armature and needed a starter. I called a friend and he said "if the starter is spinning normally but not engaging, its probably got proper continuity and not a wiring issue".

Now for the bs. I fumbled my way with removing the starter using a rediculious setup (had 16mm nuts on it? and could not find a 16mm wrench). Finally removed the starter, and tested on the ground. The bastard spun and poked out. I decided that since it did that, the starter was good and to plug it into the harness. With it wired up but not bolted into the trans, I cranked it and it operated as normal! I bolted her into the trans, and she just spins but doesnt mate the flywheel!

The flywheel teeth seem fine to me. Teeth on the starter are ok. I have 12v at the big terminal hot. The 8mm terminal and 10mm terminal do not have 12v koeo. The 8mm greenblack wire ohm tested to have continuity from starter to the pcm. The black yellow wire I have no clue.

I couldn't find a wiring diagram that had all 3 wires in it to trace them back to make sure they arent open. I think its a circuit issue between the 8mm or 10mm wire not getting power, so the armature cannot get powered to poke out.

Any ideas? Any actual wiring diagrams? Wedophone diagram only shows one wire.

Appreciate the input after a lengthy post, just trying to get my moms e34 back on the road.

[Kozworth]

On a side note of what I am trying today.

The two smaller wires to the solenoid should have 12v at the START position correct? If not, it is an open in the wiring?

[jlevie]

The green wire is the unloader relay control wire. With ignition on it should be at 0v when the starter is not engaged and go to 12v when the starter is engaged. The black/yellow wire is the starter solenoid control and goes to 12v when the key is turned to start. Unless the flywheel teeth are gone, the starter spinning and not engaging is a bad starter.

[Kozworth]

As always, thank you. Looks like I got my work on the car sorted today.

[M-technik-3]

That would be a bad Bendix...just went through that last week with the M3. Got a rebuilt one from Bosch and the key lead was wired backwards.

[Kozworth]

That would be a bad Bendix...just went through that last week with the M3. Got a rebuilt one from Bosch and the key lead was wired backwards.

That was my initial thought when I looked at the car. I figured the bendix was not pushing out.

However, with the starter bench tested, it did operate as it should. With the starter hooked up to the car but NOT in the bellhousing, just sitting outside it, it worked. However, when in the bell housing it did not. Thats why I was wondering if the wires were shorting somewhere or just causing an open when I moved the starter into the bell housing.

[M-technik-3]

Load tested the battery? has good grounds as mentioned? Wiring has good continuity? aka no internal breaks in the wire.

[Kozworth]

Havent load tested. I figured with a strong crank that the battery is outputting correct amperage and voltage. Wiring on the green black wire has continuity.

[M-technik-3]

I'm thinking bad starter.

[Kozworth]

Ok so heres the update. Put in the new starter and same deal. Just getting the bendix spinning and not mating the flywheel.

I am going out now to test for voltage on the two smaller wires.

[Kozworth]

Ok, the blk yellow wire has voltage when the car is cranked. With the green blk wire, there is no voltage when the starter just spins but does not extend. Battery is fully charged. Blk yellow wire has full continuity throughout the wiring.

I have 3 unloader relays. I am unsure of the wiring to and from the relays, and as to why there would be 3?

1st and 3rd unloader relays both have continuity on the non switch side. Both click when put into fusebox koeo. Both have full voltage at the fusebox.

The 2nd relay has 9v at the fusebox. This relay does not click when inserted into fusebox. I believe it had continuity, but with a known good relay there was still no click. I am assuming this is because the voltage is not great enough for the relay to close the switch. So I am looking for resistance on the blk green wire but, like i stated, I have no wiring diagrams for this.

[nickskater09]

I may not be understanding this fully, but it sounds like more of an issue of the flywheel/transmission being out of place than a wiring problem. Have you checked to see if the flywheel is still where it's supposed to be?

The fact that she heard a loud noise and the car stopped running makes me think something broke. Even if the starter wasn't working properly, the car shouldn't have turned off when she heard a noise.


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[golde30]

Auto or manual?

[Kozworth]

The car is auto. So yes, the starter is more of a pain with the auto trans dippy in the way, along with cooler lines.

Thats what I am thinking, something might be broke. You know how it can be diagnosing a car when the owner themselves cant really explain the point thoroughly. I am going to try rotating the crank over to see if there is just an issue with that part of the flywheel. However, it looked fine to me.

The only issue I can think that would stop the car would be a broken timing belt. Even then though, I feel that the starter would still spin the engine somewhat, until it makes contact with the bent valve. However, it just sounds like it is not mating the flywheel. I will try to get a video of it later on today.

Appreciate the input so far guys, any open ideas are welcomed. I am running low on diag ideas.

[Kozworth]

I found the answer to this. The starter was actually working fine the whole time. The issue was, the timing belt had stretched and boom went some valves. No compression=the starter spinning the flywheel with ease. This sounds IDENTICAL to just putting power to the 8mm terminal, which only spins the bendix but does not extend it.

Appreciate all the input, but shaking my head a bit that I let my mind stick to the starter all this time! Live and you learn I guess!