04F150Truck

I own a 2004 Ford F150 and have recently been having trouble with the cylinder 6 and 5. It's currently throwing the following codes: P0306, P0316, P0356, and P0355. I've replaced all spark plugs earlier this year, swapped ignition coil 6 to cylinder 1 and code did not follow. Tried wiggle testing fuel injector and ignition coil to no avail. Utilized a noid light test to determine it's not an electrical issue.

The truck has 153K miles and misfires steadily. Cam phasers, timing chains, etc were all replaced along with the passenger side exhaust manifold which helped with the misfiring and infamous ticking noise. One thing I have noticed is if I drive with the AC on, every now and then the engine light will flash and the AC will suddenly get warm giving off a humid feel. Obviously, I try not to drive the truck if I don't have to.

Anyone have any advice on what I should check next? All parts replaced were Ford OEM/Motorcraft.

KS-Glock

Did you clear all the codes after you swapped the coils? Have you pulled the plug out of those cylinders yet to see what it looks like?

04F150Truck

Didn't clear the codes, but haven't noticed any change. It still misfired. I was planning on checking the plugs tomorrow, but I doubt that's the cause since they've all been replaced. Hopefully I'm wrong.

KS-Glock

Well if you cleared the codes. It may pop up with a new code that changes thoughts. I'm getting ready to jump into the spark plug change and am not excited about that....

04F150Truck

Yeah it's not fun. My advice, take your time and use some Kroil. Also, probably going to need the Lisle spark plug remover. I still have mine if you or anyone reading this is interested.

KS-Glock

I have a tool lined up and ready to go. Wishfully hoping I won't need it...
My truck threw a P0301 and P0316 just the other day. I hope I'm not chasing codes after it all...

techrep

iTrader: (1)

Did you replace the boots and springs.. A flashing CEL indicates a misfire condition still exist .. May have a cracked plug or injector problem

04F150Truck

So in a bit of a time crunch last week, I only serviced cylinder 6 and found a cracked plug. Which is surprising since I replaced the full set already, but nevertheless I replaced it again along with the COP. Turned truck on, ran slightly better and didn't reset codes since I knew I still had to do cylinder 5.

So today I had some time and replaced the plug which looked fine and the COP, but this time when I would try to run the truck, I would only get a rapid clicking noise. The starter is basically new since it was replaced no more than 2 months ago and has less than 100 miles on it. Battery isn't that old either (about 4 months). I have the battery disconnected for about 30 minutes so far so will reconnect and see what happens.

Does anyone have some insight on why this could be happening though?

joe mcmillan

Either a low charge on the battery or a bad ground. Check all of your battery and starter connections. One is either loose or corroded causing a poor connection.

Bobby Lane

I've seen you mention the boots and spring before. I haven't replaced my COPS yet, but am getting ready to. Where do the boots and springs come into play? The videos I've looked at don't really reference them, they make it look like you pull off the old cop, put in new one. I looked for previous posts but am striking out with my searches for some reason.