2005 Ford F-150 ignition coils

Tiny
JPDEP
  • MEMBER
  • 2005 FORD F-150
  • 5.4L
  • V8
  • 4WD
  • AUTOMATIC
  • 115,000 MILES
I recently changed the plugs in my 05 f150 5.4l. Now it is running worse than before I changed the plugs. Would the ignition coils and boots need to be replaced also? I cleaned the boots and springs in them and placed fresh dielectric gel on them. I don't know what I did wrong.
Monday, October 27th, 2014 AT 4:17 PM

9 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,755 POSTS
What I have seen happen many times is the boot goes bad and the spark is partially shorted out. This results in a misfire. Tell me, is the check engine light coming on or flashing?
Was this
answer
helpful?
Yes
No
-1
Monday, October 27th, 2014 AT 6:27 PM
Tiny
JPDEP
  • MEMBER
  • 6 POSTS
Yes. It went off initially when I changed the plugs but came back on shortly after. I was able to drive it long enough to take it to an auto store to have the codes read. It said there was a problem with the coil. That's when I removed them and cleaned them. The light came on again but I haven't been able to drive the truck back to have it read again. It has no power and stalls.
Was this
answer
helpful?
Yes
No
Monday, October 27th, 2014 AT 7:22 PM
Tiny
JPDEP
  • MEMBER
  • 6 POSTS
I'm just thinking that it should've been running just as rough before I changed the plugs if the coils and boots were bad too.
Was this
answer
helpful?
Yes
No
Monday, October 27th, 2014 AT 7:26 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,755 POSTS
We need to have the computer scanned to determine the affected cylinders. That way we can focus on where the problem is coming from. Can you access a scanner? Something is telling me that the boots on the coil packs are bad and they are arcing.
Was this
answer
helpful?
Yes
No
Tuesday, October 28th, 2014 AT 5:00 AM
Tiny
JPDEP
  • MEMBER
  • 6 POSTS
Yes. I changed all of the plugs, boots and coils but now I'm having the same original problem (hesitation and skipping when excelerating) and I also notice shuttering when excelerating at about 50 MPH. What did I do wrong?
Was this
answer
helpful?
Yes
No
Monday, November 3rd, 2014 AT 5:52 PM
Tiny
JPDEP
  • MEMBER
  • 6 POSTS
I also took it to an auto store to have the codes read and it basically said the same thing. Misfires in cylinders 2&3 and other fuel performance and injection probable causes.
Was this
answer
helpful?
Yes
No
Monday, November 3rd, 2014 AT 5:55 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,755 POSTS
Is it possible for you to get me the codes they retrieved? As far as the problem, I doubt you did anything wrong. The problem was there before you did the work, correct? Have you removed cyl 2 and 3 plugs to check if they are properly gaped? If not, do that. Also, pay attention to the plug to see if it is wet with gas or is black.
Was this
answer
helpful?
Yes
No
Monday, November 3rd, 2014 AT 6:40 PM
Tiny
JPDEP
  • MEMBER
  • 6 POSTS
The codes it retrieved were P0300, P0301, P0302, P0303. No I haven't observed the problem plugs yet. This was just today. I did not have to gap them because they are the type of plugs that have the outer metal shell that forms a hood over the ignitor. (The ones that are notorious for breaking). Or are they still able to be gapped and I dint do it?
Was this
answer
helpful?
Yes
No
Monday, November 3rd, 2014 AT 7:06 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,755 POSTS
I think you should pull them and inspect. Something may have gotten on the end and causing the problem. Plus, I would like to know their condition. Are they wet, corroded.
Was this
answer
helpful?
Yes
No
Tuesday, November 4th, 2014 AT 8:46 AM

Please login or register to post a reply.

Sponsored links