I know this forum is really quiet these days, but I'm hoping someone out there will see this and can maybe give me some direction on where to go from here.
My dd 04 SVT Focus keeps having a cylinder 3 misfire. It is random on when it occurs, and will typically go away within 5-10 minutes of driving. Sometimes it happens upon start up, then will go away after a bit. Sometimes the car starts up perfectly, and then once driving the misfire will occur for awhile, but will ultimately go away.
I've replaced all spark plugs and wires with Motorcraft parts. I've replaced the cylinder 3 fuel injector. I've replaced the MAF sensor. The fuel filter has approximately 6,000 miles on it. *edit* I've also replaced the coil with a new Motorcraft coil.
I ended up taking it to a repair shop that I trust, and they are stumped. They checked fuel pressure as well as did a compression test and all returned normal results. The only thing they wonder is if it could be something internal in the engine/head as when the car is sitting there running perfect they would use their mechanics stethoscope to listen to every cylinder. They did say that when the car is sitting there and begins to misfire, cylinder 3 does have a different sound. Now is this due to the shear fact that this particular cylinder is not firing, thus the sound would be different than a normal firing cylinder? I'm not sure.
Do I need a new head? (I don't know where to get one anyways). Could it be something else intermittently going in and out (a sensor, wiring/wiring connection)?
Any and all help on where I could go from here would be greatly appreciated. If I can't get this issue figured out, I will have a sonic blue 04 SVT Focus for sale or will part it out for anyone who is interested.
My dd 04 SVT Focus keeps having a cylinder 3 misfire. It is random on when it occurs, and will typically go away within 5-10 minutes of driving. Sometimes it happens upon start up, then will go away after a bit. Sometimes the car starts up perfectly, and then once driving the misfire will occur for awhile, but will ultimately go away.
I've replaced all spark plugs and wires with Motorcraft parts. I've replaced the cylinder 3 fuel injector. I've replaced the MAF sensor. The fuel filter has approximately 6,000 miles on it. *edit* I've also replaced the coil with a new Motorcraft coil.
I ended up taking it to a repair shop that I trust, and they are stumped. They checked fuel pressure as well as did a compression test and all returned normal results. The only thing they wonder is if it could be something internal in the engine/head as when the car is sitting there running perfect they would use their mechanics stethoscope to listen to every cylinder. They did say that when the car is sitting there and begins to misfire, cylinder 3 does have a different sound. Now is this due to the shear fact that this particular cylinder is not firing, thus the sound would be different than a normal firing cylinder? I'm not sure.
Do I need a new head? (I don't know where to get one anyways). Could it be something else intermittently going in and out (a sensor, wiring/wiring connection)?
Any and all help on where I could go from here would be greatly appreciated. If I can't get this issue figured out, I will have a sonic blue 04 SVT Focus for sale or will part it out for anyone who is interested.
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