Hello all,
my truck is a 2003 5.4 7700 F150 and I have coolant pooling in the valley of the engine, misfiring etc.
So has anyone here ever used 4.6 to 5.4 adapters and installed a 4.6 intake?

I can go get a plastic replacement one and call it a day but since I have to haul the top of the engine off I am tossing around the idea of putting on an aftermarket aluminium.
I don't care about the potential of loosing torque either.

I had a similar situation, I used to own a Crown Victoria with a 4.6 that had the intake fail (plastic) so I said the "heck" with it and put on a Victor Jr intake. I never had an issue after and didn't notice any ill power losses.
Thoughts or comments? Please comment
Cheers

 

Sure its not coolant pipe that runs under manifold? Or other , or gasket?

2003 had better composite, doesnt fall apart like early ones.
Mine was fine at 200k, put on new engine, still fine at 265k.

 

Soon as I get settled into my next set of days off I will be tearing it all apart to figure out what is what. So far it looks like the front passenger side intake runner is cracked.
The misfiring of the engine is just terrible.

 

If you find it is the intake itself, you can try to hunt down a '99 intake. Those are/were metal.

 

Agreed...accurate post. I doubt it's the intake on that 03. But, and although Ford improved the composite for 03, they can still crack with time...high miles. The 03 manifold isn't bullet proof.....rather, - much improved.

I would have to guess it's the tube as well (heater core hard line). They never cured that problem during this generation. The o-rings (two) are going to fail right behind the water pump at some point. When they do, the block cavity will fill with coolant and dump over the starter before puddling on the ground....usual scenario.

Ford did eventually address the o-ring problem with the reman engines for these trucks sometime later. They began using using crimped short heater hose sections (5/8 I think) at the water pump connect. Actually Haynes/Chilton publicized that Ford release in their manuals way back when. Via black and white photo.

I followed suit back then (06-07), updating the connection myself after the o-rings failed twice on the 98. It wasn't as nice as the Ford update since I used clamps vs crimps. However, it fixed the problem permanently, no more yanking the manifold to replace those leaky o-rings.

 

I will be replacing my intake manifold tomorrow, along with new spark plugs and boots. As I was driving from San Antonio to Austin, my truck started to lose power going 70 mph on I-35. I pulled over to nearest gas station and saw that I had coolant puddling close to a spark plugs. I was able to dry up with towel and blew some air to get it all cleared out. Didn't see any spots where it was leaking. I drove another 50 miles without issue into Austin.
Once I had time I was able to see where the coolant was leaking (see pics).

Symptoms right before I found the leak:
​Truck idles rough once started and will level out after it warms up. It will occasionally surge a bit higher than normal idle in park, but will even out the idle after a few seconds.

I left with my uncle who is a mechanic and will help him replace it. I'll try to post more pics during install​​​​​​.


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Passenger side of truck, just left of alternator.

 

https://www.onlinefordpartscatalog.c...BoCW8YQAvD_BwE


When did ford make these manifolds again? I remember unavailable a few yrs ago.

 

I forgot to mention I have a 2000 F150 5.4 V8 230,000 miles. I've had the truck since 2003. The work done was regular oil changes/Tune ups, alternator, starter, idle air control valve and of course any hoses as I seen they needed replacement.