My 240 B230 carb model is increasingly refusing to idle. Sometimes it's ok but more and more it tries to idle at 3 or 400 rpm before stalling after a few seconds. Pulling the choke lever out a touch restores enough idle to make it safe to drive in traffic etc.

Dizzy cap and rotor are good, I put my new plugs in a week early to see if that will help (it didn't), no vacuum leaks, carb dashpot is properly topped off, idle solenoid operates fine, nothing obvious amis anywhere.

Just to make it worse, every time I roll it into the garage and lift the bonnet the damn thing idles at a steady 950 as if nothing has hapenned.

I think it might be related the the sudden cold weather (-3 Celsius as I write)in some way but, I admit, this is just a gut feeling with no hard data to back up.

Any ideas?

I'm readying for a Weber carb/740 B230K manifold swap (the secrets out now!) but I don't want to proceed until I have cured this in case I really cock something up!

Happy new year to all, especially my 245 brothers and sisters in 'boardland,

Big Rich.
--
The Volvoboy...he never grew up!