[greg bradbury]

CIS seem to have an uneven idle by the nature of the set up. That is to say that when the engine is at idle speed the fuel flow to the injectors is very low, so if your injector or distributor is dirty or just plain old and worn the spray pattern will be less than perfect. Fuel cleaner helps but rarely cues the problem. I run a tank of Redex often and this seems to help. Also richening up the mixture adjustment helps a lot at a sacrifice of fuel consumption and CO reading if you have to pass smog tests. If its set on the lean side it will definitely idle rough. I'd get the CO checked first. Cleaning the fuel lines probably won't help at all. Clean the outside if you like with some soapy steelo pads.