Help cranks but won't start

Technical Guidance for doing those Tricky Jobs

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Danny
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Help cranks but won't start

Postby Danny » Mon Jul 20, 2020 2:19 pm

Twice now, during a drive so normal operating temperature, my engine cranks strongly but won't start. It then clutch starts very easily after only a few metres of travel.
I'm suspecting a relay that has to be on for starting and switches off once running. (Had that problem in a previous car.) The car, an SE, has an Adaptronic piggy back so OBD2 is inoperative.

Anyone experienced that or know if there's such a relay, or other fix?

93_Clubman
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Re: Help cranks but won't start

Postby 93_Clubman » Tue Jul 21, 2020 4:12 pm

All MSM/SE manuals, including troubleshooting, but of course it could be Adaptronic piggyback related: https://drive.google.com/drive/folders/ ... 0xSNGVXMzA

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CrazyRacer
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Re: Help cranks but won't start

Postby CrazyRacer » Wed Jul 22, 2020 8:58 am

Maybe check the ignition switch.

Could be the ignition circuits get power in the run position but not in the start position.

Danny
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Re: Help cranks but won't start

Postby Danny » Wed Jul 22, 2020 9:52 am

Thanks for those. I've been trying to replicate the issue on my driveway but hasn't recurred since the second time.

I do suspect the crank sensor and ignition switch. So far I've tampered with the throttle sensor and main relay. Don't see it as a fuel issue because it clutch starts so easily.

Red_Bullet
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Re: Help cranks but won't start

Postby Red_Bullet » Wed Jul 22, 2020 9:55 am

Get the battery checked, Low voltage when cranking can cause the ECU to not run.

Danny
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Re: Help cranks but won't start

Postby Danny » Fri Jul 24, 2020 9:32 am

Hasn't recurred for a while now. Fitted a new battery as well. Oh, the suspense every time I take it out...

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CrazyRacer
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Re: Help cranks but won't start

Postby CrazyRacer » Wed Jul 29, 2020 6:28 pm

My brother has classic British cars and tells me that the anticipation of the inevitable breakdown is part of the excitement of taking them out for a drive.

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bruce
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Re: Help cranks but won't start

Postby bruce » Wed Jul 29, 2020 7:55 pm

Well, he must get a lot of excitement.

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CrazyRacer
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Re: Help cranks but won't start

Postby CrazyRacer » Thu Jul 30, 2020 12:47 pm

bruce wrote:Well, he must get a lot of excitement.


He does. Keeps the tow truck guys on speed dial to deal with the constant excitment.


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