Hi everyone!

Today my friend and I replaced the spark plugs on my truck. Managed to remove all 8 without any serious problems (woot woot).

First started it up, and all sounded fine. We did have the battery disconnected while we were working (a good few hours) so I just let it idle to allow the engine to figure itself out again.

Now the problems begin to start. If I give it a rev in Park or Neutral, its perfectly smooth even at 4,000 RPM. When its in gear, (reverse, drive, or 1+2) it runs like crap as I accelerate and occasionally on idle. Almost as if its misfiring, but there are no codes being set or a check engine light.

MAF sensor was replaced a couple days ago, so I don't believe that is the issue. Fuel and filters don't even have 20,000 miles on them yet, so that those are fairly new as well.

Any ideas what else could be causing problems? I have a hunch to believe it could be the ignition coils, but I never had they were fine on the previous set of spark plugs...
(This is my first post too, so I apologize if I some how put this on the wrong thread)

 

What brand and part number plugs did you use? Did you replace the coil boots and springs?

 

I stuck with the motorcraft SP-515 plugs and have yet to replace the coils and the springs.

 

I would replace the boots and springs, not the whole coil. They are available in kits and are relatively inexpensive.

http://www.rockauto.com/en/catalog/f...lug+boot,10150

Did you put antiseize on the plug shanks, taking care not to get it on the electrode strap?

The 2005 had a bad batch of fuel injectors, that could be a possibility.

 

We did put anti seize on the threads of the new plugs and made sure nothing got on the electrode strap.

I have read before about the bad fuel injectors. I dont think those have had to get replaced in the lifespan of the truck...

 

The antiseize does not go on the threads, it goes on the barrel between the threads and the tip. If you didn't apply it there, the next change is going to be rough, they will probably stick and break.