Hello all. I have a 2012 F150 echoboost that routinely goes into limp mode with acceleration & makes the engine light flash. It throws the code for 4th cylinder misfire, & I have had all the spark plugs & boots replaced through the dealership, with no change in performance. I can reproduce this issue on demand any time I want, yet nobody seems to be able to find out what it is to fix it. It only happens when in drive. I can put it in neutral & run it at high RPMs & never get it to go in limp mode. But, If I am driving it, I can floor it & it will run strong (as it should) for about 5 seconds or so, before going into limp mode & running with a lot less power. I have already made a weep hole & that has not helped to fix this particular problem. I remember reading somewhere that it could be O2 sensors in the intake manifold, or the throttle body. The dealer rep just told me it is probably not the throttle body, as that would set off the wrench light instead of the engine light. He states almost everything that sets off the engine light has to do with emissions. Any ideas on what I should have them check next? I am leaning towards having them check the O2 sensors & throttle body, & nothing else, as I do not want to keep replacing things that are not broken & do not fix the problem.

 

Toppdog,

I had the same issues as you. They replaced my turbo sensor and problem solved. No issues for about a year since they fixed it.

 

Is the turbo sensor something different from the O2 sensors?

 

I had similar issues as you with a 2011 Ecoboost. The dealer also couldn't reproduce the problem with a recording scanner on the computer. They asked me to come over and take a test drive with the mechanic. I found a big hill and gunned it and it started missing. At that point it showed up on his scanner. He said they wouldn't push a customer's vehicle that hard - that is probably why they can't reproduce the problem. If you've already replaced the plugs and boots, I would swap out the coil pack on the bad cylinder with another cylinder and see if the problem moves to the new cylinder. They found a bad coil pack on mine and that fixed the problem.

 

That’s a great question. I have no idea; they told me it was a bad turbo sensor.

If you read my prior post, I spent a fortune on this issue, replaced all plugs, wires, coil packs, etc., multiple times as EVERY Ford mechanic continued to tell me there was a misfire issue. I could easily reproduce the problem by hammering down to pass or especially when on a fairly steep incline. So...I took it to the dealership and had the tech hook up his scanner and go for a ride with me. I reproduced the problem with him in the truck and his scanner reading the data. Misfires everywhere. This is after replacing AND gapping and re-gapping plugs, coil packs, wires, boots, etc.

They then replaced what he said was the turbo sensor. Never a problem since. Runs like a scalded cat.

 

I’ve been chasing this problem with my 2011 stx 5.0 for a while now. At first I thought it was a transmission problem or even a motor/transmission mount. The issue is very intermittent though, and comes at random. That made me think to look into the computer system control modules. I cleared out all of the adaptive learning tables for transmission as well as all other adaptive values. Then I ran the misfire correction procedure. I even did the transmission characterization update which downloaded file online from Ford to update either pcm/tcm not sure which module holds the characterization info, maybe even bcm. Anyway, it runs a lot better, but the issue still pops up a few times a week. I’m going to try regapping all the plugs to .032 tomorrow. I’ll follow up with results.

 

im having that same issue, but I have the 5.0 coyote engine with no turbo. Misfires on 7 of 8 cylinders. Any ideas? I just installed all new plugs last week, but I gapped them to .042

im going to set them to .032 tomorrow.

 

The Coyote specifies about .050 for the gap. You are making it worse.

 

thank you. I couldn’t find correct gap specs anywhere. You weren’t kidding…much worse. Threw a P0107 at me this morning.

 

Need help. 2022 F150 with the 3.5 Ecoboost. Noticed this shuddering/ loss of power since it was brand new. Now has 2000 miles on it. Happens with light or moderate acceleration in the high gears. No codes are getting thrown so dealer doesn't know what to do. Any suggestions?