Okay while I have read the threads and I think I have some ideas I need your help. I have also tried cleaning and replacing boots which did help. With warmer weather my misfire is back. Low rpm only under load and idle. Low rpm = below 1500 rpm very noticble, by 1800 its gone. Cold weather and truck no misfire warmer weather and warm truck misfire like clockwork. However no codes and I have checked after it has misfired bad to the point of losing power and shaking the truck; well more of a thump thump thump you can hear and feel. A noticble stutter if you will.

At this point while PO changed plugs 25k ago I will check them. Re inspect everything even though COPs tested good with a meter and I did not see any cracks. I know COPs even on a tester can pass but still be bad. This feels like a bad coil, behaves like a bad coil on a dist motor.

Other thing I can think of is try 91 next time. I put 85 in by accident and truck sits sometimes for months without driving it. I normally put 87, I am in Denver so 85 is regular.

Outside of that I am stumped and frustrated there is no code. It would help with swapping coils as that will be my last step. With 10 COPs though I am not looking forward to it.

Other ideas? Why no code on these trucks? Seems like the motor would have to be dead to set one off.

 

If you can find someone with the right scanner, the misfire counters CAN be read - it just won't throw an actual code.

 

What type of scanner am I looking for? Dealer only kind of thing?

 

I'm really not sure anymore - a local mechanic should have one. But that might cost as much as one coil that you can start moving around

 

Maybe someone should sticky my thread on the scanner....

https://www.ford-trucks.com/forums/1...-features.html

 

My OBDII port Bluetooth scanner and Torque app supposedly can read the misfire counts, but I never was able to get it to do so.

My SCT programmer from 5Star read the misfire codes for me. It was nasty ole' fuel injector numbah 5.

One dang fuel injector, and it was a serious pain to get the fuel rail off and back on. Make sure you salvage any good o-rings from the old injector(s) you take off. I buggered a new one during the install.

 

See this thread, especially post #21 and following: https://www.ford-trucks.com/forums/1...bd1-obdll.html

I learned (the hard way!) to always have a pack of o-rings on hand before messing with the fuel rail. For me, it's a 20 minute drive each way to the nearest O'reilly's.

 

I got it to work on my torque pro app. You need to look in the test results section.

 

Chase a cop around to find the bad one and check the injector connections.

 

That would be the "hard" way for anyone who has the capability of reading the misfire counts.

 

Which the OP does not at this moment.