Effects of Dirty Idling Valve

hello fellow e36ers or potential e 36 buyers, welcome! Two days ago my wife was feeling sick and we were planning to make a trip to the clinic. Got into the car, started the engine with no problem but after about 3 seconds later, it stalled with the battery light lighted up.

It was a strange occurence because the battery I was told is new and I decided to restart the engine again, this time round, you can hear the engine cranking up, I managed to drive off and just about 150m later, the engine stalled again in the middle of the road. Thank God it was not a major road. Was getting irritated as my wife was unwell and this had to happen. Thank God too we were not too far away from my workshop.

After a few minutes rest, I decided to give it a go, the engine started and I managed to drive it all the way to the workshop. My usual mechanic came and restarted the engine again, this time round the engine was going through a series of high and low vibration...Vroom...silent, Vroom...silent again.

I left the car there for further diagnosis and about 3 hours later, the bill came up to $35! Apparently the idling valve was very dirty and my mechanic simply clean it up and it was running smoothly again with no hitch!

The idling vavle was extremely dark and black before this cleanup.