Ford 2001 SEL, 89K Miles, Misfire...

[PlanoFSXer]

In the last week alone I had spent almost $1400 fixing stuff (leaking coolant, rear hubs, engine mount). Now I am looking at about $1500 dollars for spark plug, wiring, and belt noise, which turned out to be something to do with the a/c unit, which had to completely redone. The misfiring isn't completely gone yet, any ideas?

[Skyhawk]

Look in the spark plug wells for oil. Oil in the plug well will ground out the spark. Can you identify which plug is misfiring? Pull the plug and look at it. Is it coated with black deposits, which indicate that it is not firing? A plug that is not firing will also be wet and smell of gasoline. If the plug is not black or wet, then you want to test the injector wiring with a noid light. Is the injector getting electricity? You should also test the plug wire. Pull it off of the plug and hold it with an insulated tool about a 1/4 inch from metal. Have an assistant crank the engine and see if you get a bright blue spark from the end of the plug wire. The spark should jump from the wire to the metal, e.g. engine block. If the wire is not sparking then the coil or the feed to the coil is faulty (new wire should be OK). If the injector is getting electricity, but the plug is dry, then the injector may not be opening and spraying fuel into the cylinder. Try the easiest things first, e.g. test the plug wire, look at the plug, look in the plug well for oil, etc. Let us know what you find.
You can also look for signs of oil fouling on the plug. That could indicate a leaking valve seal. At the milage indicated that would be unlikely, but it is possible. Is your EGR valve and system working properly? Let us know what you find.

[canbilly]

Did you check the coil pack? I had a cylinder#1 misfire. I almost gave up and traded it in, the salesman at the dealership said it was probably the coil pack. I switched it out first thing this morning, and whalah that was the problem. May i sugest getting a haynes manual, it has some trouble shooting tips in there. The guy lost a sale also.

[militarydave]

plano, texas i assume?

-dave

[PlanoFSXer]

...absolutely... and thanks for all the feedback. There were multiple issues with the vehicle, nothing that I could have fixed myself.