i have cleaned the idle speed regulating valve but how can i check whether it works or not?I also cleaned the two hoses connected to the valve.I have cleaned the throttle plate with carb cleaner.The ecu gives a fault code 2-1-2 which is the oxygen sensor.If the ecu had a fault and needed replacing would it give a fault code?My car has 94000Km, should i replace the oxygen sensor with a new one?According to the haynes manual i should check for vacuum leaks,clean the cranckshaft hoses,check the exhaust,inlet gaskets,injectors,replace the o rings,renew the fuel filter and other stuff.I have currently replaced the spark plugs and had it serviced so i assume they checked the valve clearances and other stuff i cannot do my self.Should i check the catalytic converter whether it has gone bad?The accelerator cable now that you mention it seems to stick the first time i turn the throttle by hand.I guess the clicking noise is there but i cant be 100% sure.There are so many things to check, iam drowning. What would you recommend that i should do?Thanks a lot for your intrest.