Mis fires of f450

[James Eckland]

We have a 2019 Thor z28 with the Ford f450 10 cyclinder. We keep getting check engine light and reading shows mis fires of cyclinders #2 and #9. In garage twice and mechanics can find nothing wrong. Anybody have this problem?

[Bob Denman]

Welcome to the Forum!
Are ou sure that they took a close look at all of the connections?
(I like to never assume anything...)

[taylorbob1]

Gas cap
Coils
MAP sensor (manifold absolute pressure sensor)
Oxygen sensor
Injectors
Fuel filter

The service mgr generally will do the least intrusive remedy first, with no regard of your inconvenience for unlimited follow-up visits

Good luck

[Mustang46555]

I'll add plug wires to Taylorbob's list. Things get pretty tight and hot under the E450 hood and one or two wires could be "induction firing" under load. One question however, independent garage or Ford dealership garage?

[wingnut60]

A Ford dealer would be able to hook the computer to the OBD II port and drive it to duplicate the problem and get a real idea of what the trouble is. This should be under warranty, stay on them to find it.