2013 F-150 5.0 running rough

[patperry2766]

2013 F-150 5.0L 2WD

Got a CEL and took it to parts store and their OBDII reader said cyl # 7 misfire. Truck seemed to run fine and it went away pretty quickly, so I just disregarded it.

About 3 weeks later another CEL light came on, but again it was dx'ed as cyl #7 misfire, went away pretty quickly, but I replaced the plugs anyway because of the mileage. Motorcraft factory replacements gapped to .51.

I went ahead and replaced the coil anyway about a week later and noticed my gas mileage starting to go down, about 1 1/2-2 MPG. Checked the air filter seemed to be fine with no excessive dirt build-up so I just blew it out with the compressor.

I had a brain fart and took throttle body off and cleaned it thinking it was the MAS. In my defense, it looked strikingly similar to the MAS on my wife's Escape that I've had to replace a couple of times. I didn't replace the gasket because I didn't have one.

I can't remember exactly when it appeared but the engine seemed to be running rough when in P or N, but if I have it in D with my foot on the brake, I can't sense it running rough, nor can I detect it running rough when driving.

Today, I gapped the plugs down to .49 and cleaned the real MAS, but still feel the rough idle. Should I replace the throttle body gasket to make sure I don't have a air leak? MPG is still down abnout 1 1/2-2 MPG.

I really don't want to have to take it to the dealership, any thoughts on what else I need to check?

I've considered pulling the old coil back on just to make sure I possibly didn't get a defective coil. All replacement parts have been factory Motorcraft replacements.

Any help or suggestions will be greatly appreciated

[jerem0621]

What brand coil did you use?

I used Accell coils on my V10 and had no positive results.

Go OEM on the coils if you can afford it. When I start chasing misses I change the boots and springs and if that doesn’t work I replace the coils. It can be maddening to find the right coil that is missing.

I did use aftermarket coils on my V10 from a company called Uneek Supply and the coils performed great.

Also, and JMHO... I I put dialectic grease on the connections and I normally replace ALL of the boots and springs on my coils when I change the plugs on my Ford products.

As for plug gaps I just set them per the owners manual.

Also, the fuel filter may need changed. People don’t change them anymore it seems.

Thanks!

Jeremiah

[patperry2766]

carringb wrote:
What's your current mileage, and preventative maintenance history?

I've seen a lot of parts throwing at cars that really were just past due for regular PM work.

Also did you clear the codes after changing the plugs and coil?

125K, The CEL wasn't on when I replaced the coil, it had been off for about 2 weeks. I figure that was enough restart cycles to clear anything in the system. Hasn't thrown a CEL since I replaced coil about 2 weeks ago.

I keep vehicles till the wheels fall off so I'm usually pretty good about taking care of stuff.

[turbojimmy]

My money is on a bad fuel injector. I had the same problem on my Avalanche. I replaced the coil pack, wires and plug. Still misfired. On the Chevy 5.3, misfires on the back cylinders are notorious because sediment in the fuel rail plugs the injectors. I put a new injector in it and it ran like a new truck - misfire code cleared on its own.

EDIT: I realize this is not a Chevy, but the same sediment issue could occur.

[B_O__Plenty]

Most auto parts stores have pretty unsophisticated code readers operated by former fast food employees. There is a lot more to a proper diagnosis than reading a code. Spend a few dollars for a proper diagnosis rather than just throwing parts at.
B.O.

[Old_Days]

I am not a mechanic, but maybe you got some bad gas, I would get a can of sea foam and put in the gas tank then take it on the highway.

[carringb]

What's your current mileage, and preventative maintenance history?

I've seen a lot of parts throwing at cars that really were just past due for regular PM work.

Also did you clear the codes after changing the plugs and coil?

[patperry2766]

just replaced the throttle body gasket. No change in rough idle in P or N

Swapped original coil with replacement coil to see if it might have been a bad coil, No change in rough idle either in P or N,

UUUggghhh.

pua a can of SeaFoam in tank to see if it helps clean the pipes