Hey focus community, Evan here. I have a problem with my 02 ZX3, while at idle she runs fine, but when I go to take off she starts missing, BUT she wont do it if I let the clutch slip. I know its not good for it but only way shes driveable. Ive already replaced the fuel pump and the relay, had a similar problem a few months ago and I changed plugs and wires and it fixed the issue. Then it started up again. Any ideas out there. Need help ASAP or im driving it off a cliff. I really do love my car and want her back on the road. She also misses when I hand the can to it getting on the freeway but light acceleration doesnt bother it. Could it be just a fuel filter? No CEL either which I think is odd. Just a random missfire.

 

You might want to look the coil over very carefully for cracks or carbon tracks.
Also , unplug the alternator then try driving it to see if the problem is gone or still present.

 

@hanky thanks man ill definitely give it a shot, any elaboration on how the alternator could cause the issue would be appreciated. I mean ive gone through 6 of em, but wouldnt the battery take over if the alternator is giving up? And woukdnt I get a battery light?

 

Coils are known for breaking down under load and result is misfires.

Alternators, for some reason, can/will produce voltage spikes, electrical interference, that confuse the computer. When operating properly they give no problems, but when they start to act up , they can produce problems we never expect.

Ford alternators can drive techs nuts sometimes ,especially aftermarket ones. From experience had best results getting replacement alternators right from Ford.

 

I usually get my alternators from ford as well. Ill definitely take a look but the charging system was gone through a few months ago. Ill have them look at it, its under warranty. Im going to clean the MAF and the CKP sensor, then do a vacuum test tomorrow. I changed the fuel filter and that has helped a little, but it still stutters under load, not as much as it used to though. So I think injectors may need to be replaced, may have gotten gunk in them. Thanks for the advice though it definitely is appreciated. Ill update soon.