Strange Stall/ No Start - Overheated coil?

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franky2fingaz
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Joined: Mon Jun 06, 2011 10:33 am
Location: PEI

Re: Strange Stall/ No Start - Overheated coil?

Post by franky2fingaz »

Great read, had the same issue last summer but it was going into storage, figured tackle this when things dry up soon. But I have to say: your Rials look AMAZING!
'80 M535i
'08 528
'15 Tacoma 6-speed
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tschultz
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Joined: Mon Nov 14, 2011 12:58 am
Location: Colorado

Re: Strange Stall/ No Start - Overheated coil?

Post by tschultz »

Thanks Franky!

Image

I have tried a few more things and found the problem to persist with a new ICU, new fuel pump, multiple combo relays, a new Coil and spare CTS.
Starting to suspect solder joints in the ECU as the root cause to my problem here.

Started 5 times in a row and then wouldn't start for about 20 minutes. Drove home just fine after. It seems to be heat related, after driving 10-15 minutes or so. I just need to take it apart and see how joints look.
http://drive4corners.com
1980 635CSi
1985 535i
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tschultz
Posts: 138
Joined: Mon Nov 14, 2011 12:58 am
Location: Colorado

Re: Strange Stall/ No Start - Overheated coil?

Post by tschultz »

Still having problems with this, even with a new ECU.

I suspect I am having issues with the Pulse Generator inside the distributor if my new rotor doesn't make a difference... :evil:
http://drive4corners.com
1980 635CSi
1985 535i
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tschultz
Posts: 138
Joined: Mon Nov 14, 2011 12:58 am
Location: Colorado

Re: Strange Stall/ No Start - Overheated coil?

Post by tschultz »

tschultz wrote: Mon Jul 20, 2020 10:57 am The other week I was able to try out the car after suspecting the impulse sender being the problem. I thought my spare distributor was bad but it turns out that the replacement ignition control module was causing my issues. With the original ICU box in place, original ECU, original coil, the car was able to start and run. I put in the new ballast resistor and tested all three of my combo relays. However that combination is what stalled out on me earlier this week while idling in a parking lot.

With the spare distributor I was able to get it to run so I knew the problem had to be with spark somewhere between ballast resistor and distributor.
I think the original distributor/pulse generator was going bad and intermittently working. This was what was happening at the race track when it seemed to be sputtering a bit and then stalled (11/2018!!)

I drove it around today for about 30 minutes and pushed it pretty hard without misfire or stuttering/stalling. In the past it would sometimes stall when trying to accelerate hard-- so I am hopeful that this was the resolution. A great win for the 10 year ownership I have with this car!

At the gas station I got a compliment which is always pretty neat. The new raid wheel feels great! It does seem that maybe I should replace the steering link which has some play-- funds are tight so I will have to figure out when. The M90 and euro exhaust sounds great and it is such a great sound to hear again!

Some photos from the other night when it stalled out. I put the BBS RS wheels on... as I wanted the Rials on the 535is Turbo for a mountain drive

Image

Image

Image

Not impressed as the car stalled while I was taking this photo

Image

Seems pulse generator may have been the problem along with the repalcement ICU that stopped working shortly after install.


Any ideas on if there is a different distributor advance between euro and US spec distributors?

EDIT:

I found this for my euro M90 distributor:
Image
http://drive4corners.com
1980 635CSi
1985 535i
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10ringarcher
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Joined: Sun Dec 27, 2015 12:26 am
Location: NY

Re: Strange Stall/ No Start - Overheated coil?

Post by 10ringarcher »

Maybe just a bad ignition switch??
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tschultz
Posts: 138
Joined: Mon Nov 14, 2011 12:58 am
Location: Colorado

Re: Strange Stall/ No Start - Overheated coil?

Post by tschultz »

It seems the problem was a bad pulse generator/distributor. compounding the problem was the replacement ICM box seemed to stop working. I thought I replaced it last year and it worked, but it is possible I am misremembering.
http://drive4corners.com
1980 635CSi
1985 535i
Bert Poliakoff
Posts: 227
Joined: Tue Jan 06, 2009 7:13 pm

Re: Strange Stall/ No Start - Overheated coil?

Post by Bert Poliakoff »

Tom, if you are running an Ljet distributor, inside of it is a part called a "pulse generator. That is what the ECU gets it's fueling feedback from. They are known to go bad. I think you have to throw that in the mix. Yes, coils go bad otherwise why would there be such a vast amount of new coils available. The impedence of the coils does have to be correct for your system as someone else has said.
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tschultz
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Joined: Mon Nov 14, 2011 12:58 am
Location: Colorado

Re: Strange Stall/ No Start - Overheated coil?

Post by tschultz »

Thank Bert.

I know a used one resolved my running issue. Is there any way to test the pulse generator to know if it is operational or faulty?
http://drive4corners.com
1980 635CSi
1985 535i
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