Need help with PO 300 code
The problem started this way: I was driving the car, a 99 C-5 for about 7 miles when the engine started missing. Turned around and limped home and parked it. Next day it ran ok for about 3 or 4 miles and then the same problem reoccured. Back to the barn and let it sit. I went through this routine several times with the distance that it ran getting progressively less each time. I pulled up a PO303 code-cyl 3 misfire detected. Right now if I start it it will run on 4 cylinders, The four on the passengers side all fire and the four on the drivers side are all dead. Checked the ignition fuses and both are good. In fact checked every fuse in there and they are all good. I can hear the injectors working, don't think it is a fuel problem, I know the fuel pump is working. Put in new plugs when the problem occured, car has about 21,000 on it. I figure that someone else has been down this road before and might be able to shed some light on the problem. Thanks for the imput. Don
-David
And try the C5 section





