Hi all. I am driving my dads 2014 F-250 Lariat and am getting random misfire codes on 2 & 8. Here's the thing, this truck only has 5000 miles on it and already had the engine replaced at around 3000 miles when it mysteriously blew. Dad had told me the engine light was on since the replacement but was too ill to do anything about it and didn't want to take it back to the dealer because he said they were morons. I want o know if it would be a waste of time to take it back to the dealer and try to get them to correct the issue or if I should just have it fixed myself. Obviously the original 3/36 warranty is up but I'm hoping they might look at when the engine was replaced and go from there. Does anyone think I should try to argue it with the dealer? Does anybody have any idea what it could be? Any help is appreciated.

 

What troubleshooting have you done? There are a few different issues that can lead to a misfire code. If it’s a brand new engine more than likely that’s not the problem.

— Dave

 

I don't know your dealer, but I would take it in and have them take a look at it. Was the engine replaced under the 5/60 powertrain warranty?

 

take it in.....

do not mess with it..

just take it in.

and whatever paperwork you have for the engine replacement..

retired dealership mechanic ( Not Ford )

 

Is there a different Ford dealer close by that you could take it to?

If the work was done at a Ford dealership then any Ford dealer should honor the warranty.

 

Agreed, take it to a dealer, even if it's a different dealer. Warranty on the new engine should have started when they put it in, not when the truck was purchased.

 

Long story:
At about 100K miles on the odometer, and far from home. my 2017 F250 gasser developed a dead miss. Dealer couldn't get it in the shop but O'Reilly Autoparts did a scan and told me coil #6 had died. They had one in stock and I bought the few tools needed to replace it in their parking lot. Truck ran fine for awhile but then developed a miss like the OP described when accelerating very hard - like merging from a rest stop on the interstate while towing our trailer. Sometimes it would start the CEL flashing, or leave it set on.

When I got home from that cross country trip I changed all the spark plugs, which was a pain in the ***. I also bought a scan tool. Next time towing the Airstream the misfire occurred again under high load. The scan tool would turn off the CEL and tell me that either I had a random cylinder misfire or that Cylinder #1 had a misfire. I found a plug wire on E-bay, ordered it, and installed it between the plugs for Cyl. #1. Unfortunately the intermittent miss reoccurred the next time I had the truck floored while towing the trailer.

Took it to the dealer and they replaced all the plug wires, said I should have done so when replacing the plugs. Guess what? Next time towing and accelerating hard it happened again. Scan tool again pointed to cylinder #1. So I replaced the coil this time. Later I was told I could have switched coil #1 and coil #2 to see if the miss moved to cylinder #2, but so far so good - Last time I towed the Airstream and accelerated hard I had no misfire.

The misfire problem, coupled with my transmission going into limp home mode when the output speed sensor failed, was enough to make me order a replacement truck back in December. I guess that action scared the current truck and it's been behaving itself ever since. Between the trans output speed sensor and the ignition problems I probably spent over $1500 late last year. It has 110K miles on the odometer now, and hopefully will hang it there until the new truck is built.