Spent 4 hours chasing a phantom misfire on a 6.7 Cummins

Tbh I felt like a total idiot last week. I had a 2015 Dodge Ram 3500 come in with a rough idle and occasional misfire under load. I pulled codes, checked injectors, swapped fuel filters, even did a compression test. After 4 solid hours of digging and absolutely zero progress I finally noticed a tiny crack in the wiring harness near the EGR cooler. It was rubbed raw and grounding out intermittently. Just a little piece of electrical tape would have saved me half a day. Has anyone else had a gremlin like this that made you question your entire diagnostic process?

2 comments

2 Comments

lopez.quinn1mo ago

Happens to everyone. Electrical gremlins are the worst.

seanjackson1mo ago

Blame the flux capacitor.