Hello All,
I have a 99 F-150 Lariat 5.4L supercab.I recently had a spark plug blow out of the head, I have heard this is somewhat a common problem in the late 90's and early 2000's F150s.Does anyone know the cause and the fix to this problem?
I also want to get more power out of this engine,besides a chip tuner, cold air intake and larger throttle body;give me opinions on the following ideas:
1)Porting the heads or buying new ported heads.
2)Repacing the engine totally with a new crate motor.(current miles 122k)
a)Will a new 3v engine fit in my 99, if so what changes would have to be made?
b)Would a 4v 5.4L Navigator engine work in my F150 and what would be involved in changing it over to this engine?

The bottom line is that I love my truck but hate the power or should I say the lack of!!!
Thanks,
Dan

 

That's a common problem when do it yourselfers try to chnage there own plugs .

The 5.4L is a GREAT motor , Plenty of power.

You not only don't know what your doing , You also don't know what your talking about ..

Explains your problem , clearly..

 

Here's a recent thread on the plug problem.

https://www.f150online.com/forums/sh...d.php?t=264370

Good luck.

 

For your info "O WISE ONE", I had the truck tuned by a NAPA certified mechanic. I didn't feel like going through the hassle of changing the plugs myself due to time constraints and the pain in the *** it is.If you would like to put my mechanic skills to the test; I've got an 03 COBRA that I have modded and tuned myself;if you have something in your yard you want put up against it,just let me know homeboy!!!!!!
As far as the 5.4, Ford somewhat dropped the ball with the power until the 04 3v engines.You have a big engine like the 5.4 with such little power!!!!Give me a break, you sound like you need a 4 cyl if you think the 5.4 has enough power!!!!!!!

 

Thanks alot for the helpful info, I really appreciate it.
Take Care.

 

This one's good, turned out very successful..Even an idiot can follow


https://www.f150online.com/forums/sh...d.php?t=265181

 

the plugs blowing have nothing to do with do it yourselfers trying to change the plugs. its a Ford defect of assembly problem.

Here is a very informative thread with alot of info. this one helped me with my problem three years ago.

There was a Class action filed against Ford but, both the Federal one in St. Louis and the state one in California have been dismissed.

 

Good Luck

 

If it were me, I would sert all 8 plug holes, have the heads ported while you have them out, throw in a set of Crane 102500 cams (cheap with a good grind), clean up the intake, gasket match everything, throw on a bigger throttle body, some long-tube headers, hi-flow cat's on a custom y, dual 3" all the way back, and have it dyno tuned. But, well, that's just me. LOL!

 

Got you covered on the exhaust. I had hi-flow cats and Flowmasters installed over a year ago.My next step is going to be a BBK throttle body with a K&N cold air intake and probably a chip tuner.Do you know if a 4v 1999 Navigator motor will fit in these trucks?:thumbsup

 

The 5.4 is a great motor, it comes with enough power to do the job - NO, it's not a COBRA Dumb a^^ , What a comparison lol - Why did you get truck - to biatch about it , what an a^^ .. Yeah, Ford dropped the ball alright - as you were walkin by...
I'm not going to give you a brake, it sounds like you need a pacifier, yuh wine like a freaken baby..

5.4L's a good motor stock, it has been for me since 1998, You hook that COBRA to my back bumper and be chitten your pant's "homeboy"

 

jbrew, what is your problem?

I find even when using it as a truck (ie hooked to a 9000 lb tailer with 85' of frontal area) even the 24V 5.4L to be a bit down on power compared to a GM 6.0L or DC 5.7L.

If the 5.4L 16V has "enough power to do the job" I guess Ford is wasting their their time with the 24V, 6.8L V-10, and the International Diesels. After all the the 5.4L 16V has enough "power to do the job". Might be true. Some of us however much prefer to yank 80,000 lb with a 600 bhp CAT C16 instead of an old 250 bhp 855ci Cummins SC.

 

My problem , My major problem !! Is you guys cutting down the 5.4 when you don't need to - you need to pull that much , buy a diesel or something . People come here and ask for help and that's fine , that's what it's all about - thats it!! .. It cheezes me off big time , people fly in here with there freakin cutdowns ..Its bull !!

 

I'm not cutting the engine down. I knew when I bought it (5.4L 24V) that it was a bit weaker than a GM 5.3L in bhp but had a better power curve for towing. Now on the new trucks GM is offering a 6.0L 367 bhp engine in the 1500. It makes more power everywhere than the 24V 5.4L

I also new that it was down on power to a DC 5.7L almost everywhere. Some will tell you the 5.7L lacks power down low but it doesnt. It just has more high-end kick than most truck motors.

So why did I buy the Ford? I liked the handling and ride better. Its a good truck but some people just want a bit more power. Thats not a cut down. I have no plans to make major mods to my 5.4L 24V but I can understand if the kids want a bit more "ommph".

If I do anything to mine it will be exhaust, intake , and tuning. Exhaust because I like a little more rumble, intake "just because", and tuning because for the life of me I cant understand why a engine that redlines at 5400 rpm shifts at 4800 rpm.

 

Yup, it will. Same block duder.