Hi Guys,

My 2018 F150 3.5 is going through spark plugs like crazy. I will start to get a misfire after a certain amount of time. I will then replace my plugs and will run like a top for about a 1000 miles. Then slowly degrade in performance until I have to change the plugs again. I've been putting in NGK Iridium's. I here you should stick with OEMs, but Iridium is better that platinum, which is what the Motorcraft SP-594 is. So I don't think its the plugs, but who knows. I also believe if it was the coil packs, I would get immediate feedback regardless of replacing my plugs. Not have to wait a month to find out. Not one plug that I replaced looked bad either. FYI, I did the weep hole about 1000 miles ago too. Any thoughts. Thanks!

 

Post a good photo showing the plugs that you have removed. Special attention to the Electrode and Porcelain color. What gas are you running? Are you high altitude?
What DTCs do you have?

 

Hi, here are the pictures. I am running 87 with 10% ethanol. No high altitude. A 1000 miles ago I was just getting the P036, etc. Misfire codes. Yesterday. My truck flashed the engine light a bunch of times, but went away after a half mile. Based on its past shuttering, I kinda figured what it was and just replaced the plugs. Still no shuttering today.

 

Hi, here are the pictures. I am running 87 with 10% ethanol. No high altitude. A 1000 miles ago I was just getting the P036, etc. Misfire codes. Yesterday. My truck flashed the engine light a bunch of times, but went away after a half mile. Based on its past shuttering, I kinda figured what it was and just replaced the plugs. Still no shuttering today.

 

In my opinion there is nothing wrong with those plugs. My guess is the rubber boots on the COPs may need replacement. Misfires need to reach a certain level before they will set a code and you may be below that threshold. P0036 does not indicate misfires, its an oxygen sensor code. Sorry I do not any solutions for you.

 

I honestly cannot remember what the exact codes were. It was a month ago. I just remember it was multiple misfire codes. I will give the boots a try. They looked good, but there cheap and worth a try. Thanks for your help.

 

Get your codes read again and post them. Autozone and others do this for free. Do not follow their recommended fixes unless you like spending money. Often times their fixes are not the most direct path to a solution. Post back here for solutions and advice.

 

If my truck automatically cleared the check engine light itself and no light is currently on, will the computer still hold codes?

 

I am not totally sure about a momentary CEL but likely they will still be there and some may show as pending.

 

No codes, unfortunately.