5.4l Spark Plugs

[MarkT]

Everybody has probably heard one story or another about the Ford 5.4l spark plugs issues.

The early 5.4 engines had only about 4 threads holding the plugs in and sometimes the threads would strip and the plug would shoot out of the head. Ford added more threads on later models to solve the problem.

Then in 2004 came the 3V Triton engine with an unconventional spark plug design... plenty of threads but it had a long shielded center electrode below the threads. At high mileages, sometimes the shield would seize in the head. There was also a weak spot where the shield attached below the threads caused by the manufacturing technique ("two piece design"). The end result? The spark plug would unthread just fine but the electrode shield would snap off and stay in the head. Ouch!

There is a Ford TSB on spark plug removal and tools available to extract the broken shield if it snaps off. Champion also came out with a new manufacturing technique ("one piece design") which makes the shield attachment much stronger and breakage far less likely.



The good news is that in 2008 Ford redesigned the spark plugs yet again. The spark plugs in our Raptors are a more conventional design without the long shield and with plenty of threads to prevent thread stripping. Problem solved!

 

[FSM06]

That's an excellent point Mark and comforting to know that after extracting sooooooo many of these shields and lower porcelain portions of the 04' to 08' 3V design that it won't be an issue in the Raptor. I was ecstatic to see Ford went back to the more conventional design.

 

[BigJ]

Great info! I had heard of the issues, but had no idea of the history, nor the most recent redesign.

Thanks Mark!

 

[jesse]

EXCELLENT info~! although i never had a problem with my 2005 5.4, it ended up having close to 80K before i traded her in for my Raptor....which helped my decision on the 5.4...i just know this mill is kick ass and durable. Forgot to mention, i never replaced my plugs on it either LOL i abused the hell out of that truck, to include never changing the air filter till 20K, also never changed the coolant...or the power steering fluid...and it still ran like a champ! LOL

 

[Falcon]

One problem I have experienced several times on my 01 5.4L with 140,000 miles is plugs shorting out. No. 6 is laying down now. I have a buddy who is a great mechanic, and he said it was the coil pack shorting down the ceramic to the block... once it started by water getting past the boot, it makes an arc trail and it continues to short out even when dry until you change the boot and or plug. Does that make sense to you, and are there any problems remaining from that issue?

Falcon

 

[SVTRay]

Then in 2004 came the 3V Triton engine with an unconventional spark plug design... plenty of threads

Ford actually started correcting this problem in 2003 with the regular 2v heads by issuing 8 thread plug heads.

 

[The Tank]

Ford actually started correcting this problem in 2003 with the regular 2v heads by issuing 8 thread plug heads.

It was mid 2001 the Lightnings and some Mustangs were the first to get the new heads and the number of threads wasn't the problem it was over tightening from the factory and then it got on the internet and people went out and tightened them even more. My tuners Lightning is on 4 thread heads has never blown a plug out and it makes about 500hp.

 

[ifixcopcars]

As far as removing the coils, remove the wire connector and unbolt the coil, twist the coil to "unstick" the boot in the head. I fix cop cars, mostly crown vic's, 4.6, for a living and have never had a problem removing the coils. If the boot comes off the coil, use some needle nose pliers and pull it out of the head. I always replace the boots and contact springs inside when I change spark plugs. They tend to shrink over time from the heat, sometimes crack and if the area gets wet, they short out. You can buy the boots and contact springs at most major auto parts store, I use ones marketed by Standard Motor Products, USA made. If you actually need a new coil, buy the US made units, the import junk is just that and don't spend extra for name brand high performance coils, they are no better than oe replacements, just got a pedigree name and high price. When you install new spark plugs use a little anti-seize on the threads.