New member, long time Ford owner. I have had my 2005 F150 KR 80,000 miles, no mods up for sale for about 2 months now. I have had 3 lookers take it out and every one has come back with the check engine light on. Codes read P03XX. It changes every time it trips. So I did some reading on the codes and it is alway a misfire and a different cylider.

This never happens when I drive it so I asked the last guy what he was doing and he said he came to a stop and gunned it. It took off then hesitated on him. The longer he held it to the floor the more it hesitated. So I cleared the codes and took it for a spin. I was able to reproduce the code and it shows a different cylider misfire now. I read this forum and learned about the plug issues and I am a little scared to perform the work now. So I purchased new boots and springs and some dielectric grease and figured I would clean the coils and replace the boots and grease.

Now it is running rougher, even at idle. I unplugged each coil pack while running but it sounded like the engine got worse with each one I removed so I couldnt figure out which was causing the problem.

How do you know the spring is seated properly on the plug tip?

Should I apply dielectric to both ends of the spring (coil and plug side)?

I cleaned the MAF after the first time it happened but that didn't help. Will take in for new plugs tomorrow and I am ordering coil packs today. Would just like to sell this truck and move on to the next one but this issue is scaring everyone away.

Thanks in advance for your help.

John

 

if you go to a ford dealer they have a diaognostic test that is way more advanced then you can get at a local shop. its realtively expensive (120) but it can tell you exactly what part of your engine is struggling. it will pinpoint the cylinder, sparkplug, coil pack or the exact cause instead of getting a regular diaognostic that gives you a general idea of a problem. im sure if you talk to the service rep and tell him that youll get the work done at the dealer, hell drop the fee to run the test

 

I also have that problem,but my 2006 f-150 Lariet is popping under a load.I changed the fuel pump and filter,but still have about 27lbs of pressure. What do you think could be causing this problem?

 

I am going to try to get it in at the dealer on Monday. I want them to do the plugs so that if anything happens I can join in on the lawsuit. I wish I would have read this forum before I purchased the truck 2 years ago.

I am ordering aftermarket coils. $115/set delivered vs. $58 each for the Motorcraft at O'Rielly. I want it running right when I sell it. Other than this problem it has been a very reliable truck.

Thanks for the input.

 

Well, I installed the new coils last night. The truck is not missing as much but when I get on it it still does stumble. I wanted to wait for the coil packs before I brought it in for plugs so it is going in tomorrow. I cleared the codes and came up with some new ones:

P0300
P0351
P0352
P0355
P0356
P0357
P0358

These are all the same thing. They suggest the coil pack is faulty. I have read that the PCM may have a faulty wire. Anybody else out there that can confirm this?

 

to boss, ur pressure problem my be the module above the spare tire on the cross member, i had to change mine, these thing tend to break and the water gets in