I have a ford mondeo 1.8 r reg which has been converted to gas before i got it. it overheats when idling but the temp needle only goes up to about half way it blow the head gasket and just had that replaced and head skimmed and valves done but it still overheats i can see bubbles comming up through the expansion tank before it overheats and have flushed the system through and changed the temp gauge and thermastat and fan switch. i also changed the idle speed control valve as it was rough when ticking over and now the revs go up to 3-4000 constantly can anyone help please.
Sounds to me like the fuel/air ratio is wrong, too little fuel in the mixture makes an engine rev higher at idle but with less power, and generally it will stall as soon as you put some load on it.
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