Hi, we had this car come in 3 days ago as it was running rough but not really a misfire, it wont rev up and pops back through the inlet. it seems to be worse when its cold. heres the catch, its intermittent
you can start it up and it runs like a pig, switch it off and on again and its perfect. i have noticed that if you touch the throttle when starting it plays up, if you dont touch it its fine. scanned for codes using modis, there are no codes. i have checked live data but nothing looks odd, i have scoped airmass, temp sensor, crank sensor, cam sensor, egr valve and lamdas i have also checked coil pack, fuel pressure and valve timing, every thing looks as it should. i have checked sensors when running ok and not and they dont change. i dont know how to check throttle body / stepper motor. any help or ideas would be much appreciated as its now driving me nuts.
many thanks kev.