I have a 1981 Volvo 245 GLE with Kjet fuel injection witch has developed a intermittent misfire at idle and seems to do it a bit when you pull away from the lights, it seems to run very well otherwise, has good power. and is good on gas I have replaced plugs, HT leads, dizzy cap, injector O rings, tried a different IGN coil, Plugs look like it has been running lean, I don't have any way to check the fuel pressure, but I have enough spare parts to replace most of the K jet system. the air control valve seemed to have a hole in the top by that small nut is that ok? I smoked some tea leaves and blew the smoke in the vacume advance tube and it was comming out that hole witch looks like it shouldn't be there. What elce should I check? any good DIY tips?
Here is how it works http://www.k-jet.org/articles/information/k-jet-in-detail/