cylinder 6 misfire

[73stallion]

so yesterday my '99 finally triggered the check engine light. i know i have an occasional misfire in the #6 cylinder, but don't know why.

i do have a faulty fuel pressure regulator. what's the chance of that being the problem? it is the farthest injector from the regulator. it primarily misses upon cold start. it's also occasionally misses while cruising under mild to light acceleration. supposedly the PO replaced the plugs, wires, and coil pack. he also said he replaced the air filter which i found not to be true.

 

[Blacksheep Josh]

if you know the regulator is faulty, go ahead and change it. might fix it, might not, but at least that part would be fixed.

 

[aldive]

Have you replaced the #6 plug? wire?

Have you checked the coilpack?

 

[73stallion]

there's another question, how do you check a coil pack? supposedly he replaced it, but....

 

[73stallion]

well i checked the coil pack this morning and it's fine. pulled the plug and it's got platinum plugs, those are leaving! i'm gonna install autolite 103's either later today or in the morning.

 

[73stallion]

update, problem fixed. i replaced the bosch platinums with autolite 103's, no more misfire. runs stronger and it's starting up a lot easier too.

 

[96eb96]

update, problem fixed. i replaced the bosch platinums with autolite 103's, no more misfire. runs stronger and it's starting up a lot easier too.

I notice on all Ford sites that Bosch plugs give issues in Ford engines. Stick to Motorcraft or Autolite as a secondary aftermarket.