Rob-150

I have a 2006 Ford f-150 with the 5.4L engine. I keep getting a code of cylinder #5 misfire. Also when I drive it i can tell there is a miss, and when I get to about 4,000 RPMs in 2nd gear it will just fall on its face and the engine light will just start flashing on and off. So i thought Coil. I change the spark plug and Coil the problem continued. I have also changed the fuel filter and the injector on the #5 spot (front drivers side) and the problem continues. Please help I am running out of ideas.?.?

Javi_F-150

Check your cats.

Timbo82012

Same problem here. Did you get it fixed? How do you check the cats?

Rob-150

I tryed the cats and it didn't fix, so I ended up giving up and took it to the dealer they fixed the problem after about two weeks of troubleshooting... it was explained to me that they had to take the intake off and there was a valve that was not operating correctly and for some reason it only affected the # 5 cylinder... that's all I know good luck I know this was a long and expensive headache for me...

Timbo82012

If you dont mind me asking. How much did that run you?

Timbo82012

I tried several different cops on my misfire and it never solved the problem so i broke down and took it to the dealership. They called me and advised it was the cop. I told them i had switched out several and it didnt help. Long story short, there is some kind of rubber piece in the connector that was folded back and causing all the cops i put on that cylinder to malfunction. The rubber piece was fixed and i put a new cop on it and it runs fine now

Dealership charged me 145.00 to figure that out. Was going to charge me 60.00 labor to put a new one on and 85.00 for the cop.
I bought a good quality cop for 50.00 and put the cop on myself ( it took a whole 5min to do).

srwoodring

I have the exact same issue..... I have swapped the COP, the injector, and installed new spark plugs....what is the cats? and how do you check it?

Timbo82012

Cats=catalytic converters. If its cats, i would think it would be more then one cylinder misfiring. It maybe the same sitiation i had Does the connector slide on the cop easily or is it kinda difficult to get it to snap on?