5.4L coil paks...

rockcity

rockcity

everyday is a chance to get better
Joined
Apr 10, 2005
Location
Greenville, NC
OK, I've replaced about half of my coil packs on my 2000 F250 about 2 months ago. It ran like a brand new truck and I loved it. The other week I went on vacation for 10 days. I came back and, since I have a company vehicle, let my truck sit for another 10 days or so. OK, I get in the truck and now I seem like I have the same problem, only slightly worse.

could the other coil paks have gone bad during that 20 days of sitting? Could something else be causing the new coil paks to be going bad?

I've taken it to my mechanic, but the only thing electronic he really can diagnose is if it comes up on the computer and my truck isn't throwing any codes.

Has anyone else had this issue and have any further suggestions to keep the coil paks from going bad and breaking the bank?

Thanks
 
It is/was a huge problem for Ford.
Im betting only 1 is bad.

Thing is its random as hell.
Me and my old man bought 03 5.4s within a week of each others. In 3 years time we each had 150k on them. He had replaced 13 packs (so some more than once) Id never had one go bad. WTF.
 
yeah, I don't get it...

right now its got 156K on it now and I just hate spending the $$$ on the coil paks. I guess once I get them all replaced it should be good for a while, I hope.

I'm just wondering what makes them go bad...
 
PS ONLY use motorcraft plugs. I went through a couple of cp's and they kept telling me it was the Bosch plugs, never would have thought it. Never replacemd another cp after that.
 
i don't know about plug types but a poor plug will kill a coil pack, if you have arching rings on yours plugs get them out and as snappy said you should just put in motocraft ones to be sure.
 
plugs are motorcraft (at least they should be as thats what I requested to be put in...) and only have about 1000 miles on them.
 
I turn wrenches for a living, I know I'me not a new memeber, the computer should tell you if there is a bad plug, wire, or coil pack. It should tell you which one at the same time. If it is the timing chain is bad, anyone can replace it, but the dealer has to reset the cams.
 
The computer isn't reading anything about the coil paks, wires or plugs.

are you saying the timing chain may be bad since I'm not reading any codes?
 
they did circle the problem, Rob:flipoff2:



like Ron said, it's just random and I don't know the reason/cause for it...
there seem to be a lot of smart guys over at http://www.f150forum.com/ if you wanna give that a shot
 
I would double check to make sure you have motorcraft platinum plugs. (due to be changed every 100k miles)

Also I had an issue with coil packs on an 5.4 f-150, I eventually found that water was getting past the boot on the coil pack and causing (cyl. #8) it to misfire. I put a new coil pack with a new boot on it and it cleared up. I was also told that there was some type of TSB on cyl 7 where the heater hose runs above the coil and could leak antifreeze on top of the coil which in turn slipped past the boot and caused a misfire. There is supposed to be a way to relocate the heater hose.

Also if it is a coil misfireing then it will set a code, especially if it is bad enough to stall the engine. If you don't have a misfire code than you are probably looking at a different problem.
 
plugs are new and are motorcraft. I'll have to double check the codes to see if a misfire code is coming up. There was one before but I haven't dealt with the truck in a week or more so I'll have to check again.
 
To find a missfire on the Ford you have to use a scan-tool that goes into Mode6 which has a PID for each section of the PCM. If you went on vacation and came home to a miss you might have coolant leaking from the right rear of the engine from the heater hoses. The factory crimp clamps suck and leak when they are cold and run coolant in the last 2 cylinders which would be bank 1 but the passenger side of the engine. I would pull the last 2 coils out on that side to see if that might be the case before I bought anymore parts.
 
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