Problem with my 2005 F-150 Truck

ford
f150

#1

Last July our 2005 Ford Lariat F150 with a 5.4 Triton engine which had 87,000 miles started to run rough. We took the vehicle to the dealership & their tests found #3 misfiring & #4 in mode 6. They completed a whole tune up and replaced #3 coil. While taking out the #3 plug, it broke and they had to restract the plug to complete the tune-up. They also performed a fuel induction service. Additionally, I had the transmission serviced. Since the tune-up, the truck idles rough & vibrates the truck. We have taken the truck back to the dealership, they hooked it up to the computer but it did not find a problem.

Any suggestions on what might be the problem.


#2

Possibly they disconnected a vacuum line and forgot to hook it back up. Or they got a couple of spark plug wires mixed up.


#3

I like Keith’s suggestions.
Since there is a problem at idle, I’m going to eliminate the transmission from the problem list. And since what they touched was spark plugs, that’s a good place to look first. Don’t let them off the hook just because their computer says nothing.
The fuel induction service is also known as a wallet vacuuming.


#4

If the truck is running rough, and they can’t find anything wrong, those guys are idiots

As far as diagnosing and using a scanner, I suspect they just know how to retrieve fault codes and nothing else

After you get this resolved, don’t bring the truck back there again


#5

Ford has had serious problems with spark plugs blowing out of their holes in these engines as well as spark plug removal problems with these engines duet o carbon buildup. Technical Service Bulletins have been issued by Ford for these problems defining how to deal with these issues, including a special procedure for spark plug removal.

I’m curious as to exactly what they did to deal with the broken plug as well as whether they performed the soak defined in Ford’s TSB before removal or just went at the plugs with a ham-fisted wrencher.

I’m also wondering of the engine is shaking at idle when it’s in neutral as well as when it’s in drive. If it smooths out in neutral, it could well be a tranny problem. I’m assuming it’s an automatic. please correct me if I’m wrong.

It’s a coil-on-plug setup, so crossing wires is not a possibility.

My concerns right now would be that broken plug; how did they fix that, a possible vacuum leak, an improper coil, and possibly even a fuel metering problem due to that “induction servicing”. I’m wondering exactly what that consisted of.

Post some answers and we’ll be able to better define likely possibilities.