A couple of months ago I got a “check engine” light and the codes came up as P1240, Injector Circuit open cyl 4 and P1228, Injector Circuit Cyl 4 short to circuit. The codes will go away and come back. I’ve checked the circuits on the wiring and all ohms out ok. If I reset the codes the car will run great for 5 to 60 miles then the car will start missing again and the codes re-appear. Could it possibly be the actual injector? If so, why does it run great if I reset the codes? What am I missing? Seems like it should be a simple fix but I’m stymied Suggestions anyone???
It could be that the wiring, like a human hair, inside the injector is breaking down electrically due to heat.
Clearing the codes may not be what causes the car to run fine for a while. The improvement is probably due to the fact that the injector has cooled in the interim.
To a lesser extent, heat can also affect wire connector terminals. (Injector plug, ECM plug, etc.)
Thanks Ok…i’ll give it a shot and let you know …cheers