my dad has a 99 E-250 with a 5.4 in it, he want to know where the plugs are? i can't see them are the a pain to change? does anyone have a diagram of the motor so we can see where the plugs are? thanks
fuzzy

 

I have the 4.6L in my '99 and just changed the plugs today. I don't know how similar it is to the 5.4L but I just followed the fat wires. The top of the wire boot has sort of egg shaped/semi circle rubber flaps. The plugs alternate with the injectors in a line, front to back.

I had to loosen the fuel lines to the injectors to get enough clearance. Just two screws (on each side of the V8) and pop the tube off the injectors. Don't let one of the O rings flop away or you will have to go to the parts store and buy a set of 8 for $11.88 like I did.

The book that comes with the van says there are different part number plugs on the left side verses the right side. I checked and it is because Ford was being cheap and put platinum on only one of the electrodes. On one side of the V8 the spark goes from center to tip, on the other it goes from tip to center. The replacement plugs have platinum on both sides so it doesn't matter which side of the engine you put them in on.

I had a problem getting the boot back on because I couldn't push down hard enough. The boot forms a tight fit with the manifold or whatever the plug goes through. I sprayed a little WD-40 on the boot where it contacts the manifold and then it would slip right into the hole.

One thing I did. I had problems with the spark plug socket sticking to the plug and coming off the extension when I tried to pull it out. I drilled and tapped a hole in the socket and put a #6-40 set screw in the side. It lines up with the little ball on the side of the extension. I can crank it tight so the socket always stays with the extension.

Hope this helps

PeteC