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Discussion Starter · #1 ·
I doubt my particular issue is common, but just in case:

My car (SBH37222) would start fine, but then would run rough for about 3 minutes with some black smoke at the tailpipe. Giving it a bit of throttle just resulted in more black smoke. Trying to drive it resulted in even more black smoke and barely enough power to get up a gentle incline. After a couple of minutes it would settle down and run fine.

I suspected the weakener and so unplugged its solenoid while it was running rough, but got no joy. On a whim I unplugged the solenoid for the automatic choke and bingo, nice smooth idle with no smoke. (Well, duh, all that black smoke meant it was running way too rich, not too weak.)

To make a long story short, my temperature delay unit (which instructs the solenoid to hold the choke closed for a few minutes when then engine bay temperatures are frigid) seems to think it's always frigid in Ireland (OK, there is *some* truth to that).

I've got a used replacment on order (I couldn't find them new), but for now I've simply disconnected the white/light-green wire from the temperature delay unit to the choke solenoid.

The temp delay unit is the small round can (which looks somewhat like a relay) mounted on the bulkhead/firewall next to the RH fan motor. If you need to do this, disconnect it at that end as the solenoid end of the wire shares a connector with the relay which holds the choke closed while the starter is running -- and you still need that.

Car starts great now, and I can drive away as soon as I get it in gear. :)

-- Jeff.
 

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Jeff,

My one and only piece of advice (and one which you may well have already followed) is never to assume that sensor X/solenoid Y/etc. is necessarily dead.

These cars are notorious for issues with grounding/earthing and I've had several issues that were the direct result of lack of ground. (Let's not even get into lack of power as well).

A multimeter is very often your best friend when chasing down problems where any electrical component could be involved in the mix.
 

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Discussion Starter · #3 ·
Brian --

Yeah, the workshop manual gives a nice "put it in the freezer" test for the temp delay unit -- which mine passes with flying colours.

Of course it also passes the test without going into the freezer, which is a bit of a problem. :)

But your advice is good, regardless.

Cheers,
-- Jeff.
 
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