Firstfives.org

Hey guys - I've had to leave my '79 633 outside recently with the temp dropping into the low to mid 20s overnite and when I'd try to start it in the mornings, it fires right up, but runs like it's hittin on maybe 4 or 5 cylinders and won't idle over 3-400 rpms until it finally warms up after 20+ minutes and smoothes out. This little car fires up and runs like a champ, without stumbling, when I keep it in the garage. What do you think's causing the rough idle when the weather drops below freezing and she's outside?

Thanks,

Bob G

Cold is not a fun temperature in which to be doing trouble shooting.

Check the FAQ for sensor identification. There's one up front that does coolant temp. Cold start fuel valve ( center of the log manifold ) same deal, read the FAQ. Probably o.k. if it starts.

Nemo, aux air valve, under the manifold ribs, with coolant hoses in/out. There's a cylinder in it that slides, adjusts air flow with heat. If it's crudded up it can make it idle weird, surge. Not quick and easy to completely remove, test, replace.

Cold likes more fuel for awhile. Low idle that won't rev up with the pedal, something fuel is constipated.

My simple solution would be to swap it so one of the others would be outside, ya know?