P0303 Misfire Cyl 3
#1
P0303 Misfire Cyl 3
I am pretty sure this code always means an ignition fault and not something else like an injector. Is that correct? I replaced spark plugs and still get the code. It got too dark or I'd be out there trying other stuff. I know now it's not the plug. The wires are fairly new so I'm afraid it will be a coil pack. Any wisdom? Thanks.
#2
I'm skeered of the dark also, what with all them zombies lurking in the brush.
But it is the best time to look at the coils, boots, and wiring for light from small arcs making it misfire.
Replacing the spark plug wire with another - and seeing if problem stays there at #3 is one way to look for it.
Hope #3 does not have coolant on the plug. Usually head gasket leaks are 1,2 7,8; the "end" cylinders. The "middle" cylinders - if leaking coolant, can be cracked block behind the cylinder liner.
If you want to know about codes read the RAVE shop manual. Or the Bosch ECU manual. All in links below.
But it is the best time to look at the coils, boots, and wiring for light from small arcs making it misfire.
Replacing the spark plug wire with another - and seeing if problem stays there at #3 is one way to look for it.
Hope #3 does not have coolant on the plug. Usually head gasket leaks are 1,2 7,8; the "end" cylinders. The "middle" cylinders - if leaking coolant, can be cracked block behind the cylinder liner.
If you want to know about codes read the RAVE shop manual. Or the Bosch ECU manual. All in links below.
#3
#4
I was hopeful for a few moments. There were no arcs to be seen in the dark. I messed with the cables a bit, moving them a bit looking for signs of arcs as far back as I could see. Nothing. So I started it and cleared the code. It seemed to be running just fine. Then I got a P0300, random misfire. That was replaced by the P0303, Cyl 3 misfire again. Whoever thought it was a good idea to mount the coil packs back there ought to be taken out back and beaten for a while.
#5
plugs, cable or coil pack. I would try one more new plug first, if not its time to pull out the wrenches.
One last thought, did you change the right plug? Drivers side, (american steering) second from the radiator
just as a guide
Coil Packs
Passenger Side
8 5 Top
2 3 Bottom
Driver Side Pack
61 Top
47 Bottom
Engine: Cylinders
Back of Engine
8 7
6 5
4 3
2 1
Front of Engine
One last thought, did you change the right plug? Drivers side, (american steering) second from the radiator
just as a guide
Coil Packs
Passenger Side
8 5 Top
2 3 Bottom
Driver Side Pack
61 Top
47 Bottom
Engine: Cylinders
Back of Engine
8 7
6 5
4 3
2 1
Front of Engine
#6
plugs, cable or coil pack. I would try one more new plug first, if not its time to pull out the wrenches.
One last thought, did you change the right plug? Drivers side, (american steering) second from the radiator
just as a guide
Coil Packs
Passenger Side
8 5 Top
2 3 Bottom
Driver Side Pack
61 Top
47 Bottom
Engine: Cylinders
Back of Engine
8 7
6 5
4 3
2 1
Front of Engine
One last thought, did you change the right plug? Drivers side, (american steering) second from the radiator
just as a guide
Coil Packs
Passenger Side
8 5 Top
2 3 Bottom
Driver Side Pack
61 Top
47 Bottom
Engine: Cylinders
Back of Engine
8 7
6 5
4 3
2 1
Front of Engine
#7
I changed the right plug. I have the revised cylinder number and coil pack layout diagram, but thanks for the reply. What about coil packs, should I buy the Bosch or is aftermarket okay? Should I replace both while I'm in there or just the one? Advance Auto has one that's pretty cheap compared to the Bosch. Rovers North has the Bosch available as each unit or as the assembly. Two times the price of each Bosch unit is less than the assembly together. The bracket can't be worth that much. If there's any advantages to one way or the other, I'd appreciate hearing about it. It's going to snow here soon and the Rover doesn't fit in my garage. This might not be very much fun. Thanks.
#8
#9
#10
Well, there's definitely no spark at the #3 plug. Now whether it's the wire or the coil pack. I'm leaning towards the coil pack because about a year ago I had a cyl 3 fault. I checked and cleared the code and it went away and didn't come back until this week. I figured it was just an anomaly. So now it's back to stay and I have no spark. I would think if it was the wire a year ago, it would have stayed then. More likely that an intermittent that comes back is something more complicated than a wire. I think if a wire is going to fail it would just fail. Now I'm going to order the coil packs and replace them both. I figure if I go to the trouble of replacing one, I may as well replace them both. If that's faulty thinking, let me know. I seem to remember someone posting some time ago about changing the coil packs without all the disassembly. Is that possible? Is it worth trying? Thanks.