Hello, I am planning to visit family in BC Canada aprox. 3000 miles away. I know my truck can make it there and back with no problem {2000 4.6} What Im wondering is the spark plug blow out issue happens suddenly or is there a noise or signs that I have to be aware of. The truck will get most fluid changes before I head out. Anything else? Thanks, love this site.

 

My customers have reported ticking in more than one case. Sounds like an exhaust leak. In other cases the customer has reported nothing except a good running truck. None of mine have done it so I have never experienced it myself.

I think your odds of a blown tire is much greater than a blown plug.

 

we drove our 97 4.6L lariat from San Francisco, California to B.C. Canada and back with over 100,000 miles on the clock with *NO* problem.


relax and enjoy your trip.

 

I thought it was only on the 5.4?

 

I had a plug back out about a month ago after having them inspected. I drove to Tulsa, OK and back (about 400mi total), and on the way back, I stopped to pay a toll, and I could hear a "tic, tic, tic" sound that sped up with acceleration. This was about 350mi into the trip, and at about 390mi, the plug blew out. It sounded like a popcorm popper, and the truck lost a lot of power. I had to pull over and get towed. It ruined the plug, and it also ruined that coil. The mech said that if the threads had been ruined, they would have to pull the head and put in a helicoil (sp?), which I guess puts in new new threads and is $$$. I have not had it happen since, and I recently had all of the plugs changed (incl. that one). Sorry for the long post. That's my experience.

HTH
James

 

Once again thanks alot guys. I guess Im just one of those people that kind of worry alot, and sometimes for nothing says the wife.

 

I agree; this seems to be an issue ONLY withthe 5.4l. Have not heard of anyone blowing a plug out of a 4.6l.

Mine is still going strong after 134,000 miles!

 

it happens on the triton 5.4 and more often on the v10. i herd a tic tic ticking noise and thought it was the belt. about 40 miles later it blew.i fixed it myself with a timesert kit. changed all the plugs at the same time and found #2 loose (#3 blew). this was 10k miles ago and no problem since

 

It happens on the 5.4s, but it can also theoretically happen on the 4.6s if you over-torque the spark plugs (anything past 10 ft/lbs.). I haven't seen a 4.6L with this problem.

 

It does happen on the 4.6l. The one reason we don't see it here is not as many people push their 4.6l engines as hard as people w/ the 5.4l (i.e. supercharged lightnings).

The mustang people have problems with it and Sean Hyland has seen it before and he's one of the gods of the 4.6l motor.

 

I have a 4.6L, though the blow out was probably due to mechanic's error (see my post above).

James

 

The risk of spark blowout is so small. Ford makes what, 800k 5.4L engines per year? 800k times 8 years in production = 6.4 million 5.4L engines. How many are failing, a few thousand? 50k? You have less than a 1% chance of the problem occurring to your truck over its life, let alone during a 3k mileage window. And, the chances of it occuring are even smaller on the 4.6L in which there are twice a smany 4.6L V8's because it is in more vehicles.

Relax, enjoy your trip.

 

Didn't they change the heads in later years to add more threads? Is this still a problem with '03/'04 Heritage?

 

Yes, they did. The problem before with the tritons/gt engines was that there was more thread on the spark plug than there was in the head. This seated the spark plug deep into the c.chamber. People would over torque.

 

lees99f150 --
Did you do the repair with the head ON the engine or remove the head. They claim you are able to repair it without taking the head off, but it sounds kinda scarey ( aluminum chips in the clyinder) Any info. greatly appreciated