Power loss after hard driving - sparks

[dr bob]

Re-reading your original post, you mention "reconnecting all the wires'. Generally, when a problem/symptom is presented as 'it's worked fine until I did this', my first suggestion is to revisit 'this'. In your case 'this' included the work connecting the wires. It's not clear to me exactly what was disconnected for the project, but I'd be looking hard at what might have been changed between 'worked fine' and now. Look for pinched or otherwise shorted wires as well as crossed connections.

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The starter in your pictures is different from the style I described for earlier 928 cars, so the warning about 'the other small connection' doesn't apply.

Unfortunately I don't have ready access to 944/951 current flow diagrams, so can't give you a specific diagnosis for your car. More generally, the trigger for the starter starts at terminal 50 at the ignition switch. For basic manual gearbox cars this would connect directly to the smaller terminal on the starter solenoid, also labeled 50. More modern cars add nanny functions like clutch-depressed switches to that circuit. For automatic gearbox cars, there's a 'neutral safety' switch in the circuit, often incorporated via a relay that somewhat simplifies the wiring. Look at your wiring diagrams and see what's between the ignition switch 50 and starter solenoid 50, and share back what you find.

-- If it's a simple clear path with none of the nanny/safety functions, it's simple to use your multimeter to look for continuity to 30 (battery positive) to that connection (either end) and see if the continuity remains after you release the key. Test with battery disconnected, trigger wire lifted from the solenoid.

-- The nanny/safety circuit additions make troubleshooting more interesting.

-- There's the possibility that the starter solenoid itself is damaged, and it's shorted internally between the starter motor contact and the 50 trigger connection to the solenoid. The safest check for that is a simple test with the starter out of the car, and booster cables attached to a battery. Trigger the starter by connecting the battery positive using a jumper wire or just a screwdriver to that trigger terminal 50. The starter motor should spin, and then stop when that jumper or screwdriver connection is removed. Same function as turning the key to start position then releasing it. If the starter motor continues to run, the problem is internal to the starter solenoid. Easiest solution then is to replace the starter.

[Belgian951]

Thanks again everyone for the excellent support.
I had some time to work on the car today and I'm happy to say she's driving again!

First, I checked the small wire going to the starter; I remembered that I rotated it a bit when I reinstalled the starter. So now, I just rotated it again, so the wire was further from the other connection. After setting the car back on the ground, I verfied that the continuous starter problem was solved!

With that quick win in the pocket, I opened the hood and started checking connections. AFM was ok, TPS also ok, ignition cables ok, other not-electrical stuff all ok. And then I checked the distribution cap. I removed it, and immediately noticed that a tiny hex bolt was sitting in it. Yep, the bolt from the rotor. The rotor was loose, and rotated the wrong way.

It's all my own fault too. When I did the timing belts when I first got the car, I didn't apply locktite to the threads since I figured it already had some from the factory. Big mistake it seems. I didn't have locktite on hand, but I have some at home, so I'll be sure to remove the bolt again and tighten it good with the locktite before my next drive.

Then I finished up with an oil change. It smelled of gas, and gas was also visible in it.


I still need to figure out the source of the gas as I didn't have the material to conduct the test. I also need to find out what that new rattle is I'm hearing. Sounds like some kind of metal plate is loose. Heatshield around the starter would be prime suspect since one bolt is missing.

[dr bob]

I don't want be a buzzkiller, but... I wouldn't claim victory quite yet. There's something still lurking behind the starter-runs symptom, beyond a 'moved the solenoid wire'. In my limited experience... Erratic electrical issues are the biggest challenges.

[icb]

I agree with Dr Bob in that you should be encouraged by what you found, but proceed cautiously.
There are no safety interlocks in the 944 (manual trans) starting circuit. You just have a wire from the ignition switch to the starter solenoid (the small wire).
Meaning that if there is still a hidden, intermittent fault lurking, it will be the ignition switch or the starter solenoid. Just to be safe, until you can establish whether it's really fixed for good or not, it would be a good practice to park the car using the handbrake with the transmission in neutral, so that if there is a fault and you're not there, the car won't bugger off across town or through your house on its own.
About the fuel in the oil : again I'm only suggesting possibilities, but when the ignition rotor went out of sync there would have been a lot of misfiring going on, which would result in lots of unburned fuel if you were on it at highway speeds...
Of course it could be something else already mentioned.
Good plan to change the oil, be sure to do the filter as well, and keep monitoring everything carefully until you get a clear picture of how well all the systems (ignition, induction, injection, electrical, electronic) are working. It won't be long before you are able to have confidence in your car.

[Belgian951]

Thanks for the heads up. I'll keep a close eye on the starter issue and do some more tests (including the ones described earlier in this thread). I always decouple the battery when I park the car so that's handled.

I changed the oil filter when I did the oil .