u/Kitchen_Film1904

F150 3.5 ecoboost 2014

Long history of misfires
Most recent history after a month of no issues:

Months ago: coil harnesses broken and corroded.

Cleaned
Zip ties to stay attached

1 wk ago: Performance starts going downhill, coils are old, sparks are old. Had a debilitating misfire while driving

Sparks replaced

6 days ago: driving 2 hours from home. Started driving with misfire on Cyl 4

Accelerating caused debilitating misfire on Cyl 6.

Replace coils 4 and 6 on the go

2 days ago: pending misfire code returns on Cyl 4 after disappearing. Horrible idle+misfire under heavy load

CEL comes on with pending, permanent, stored Cyl 4 misfire

Today: regressing further, idle worse, drivable.

Coil wire replaced on Cyl 4
Codes go away
Idle partially stabilized, but noticeable misfire

Driving home: misfiring under medium load, no codes

PLEASE HELP IM GOING INSANE

Cyl 4 plug came out covered in soot after only a week. My dad took it from me and used a wire brush to pretty aggressively “clean” it before I could stop him. I’m worried this could be causing something

reddit.com
u/Kitchen_Film1904 — 14 days ago