I have a 2000 4.6 and it died while driving. Now it will not start. It will try to fire. I scanned the codes and got Cyl 5 misfire. The plug wire was bad. replaced it and all the plugs. Gapped at .54. It started and ran, but when I gave it gas it died and now same thing, but no codes. If I pull one plug it will start up and run. The RPMs will be up,(no plug = big vacuum leak) put the plug back in and it will not work. I reset the computer, same thing. I will be checking the EGR valve next. Dose anyone have any Ideas or know issues with this motor I may be missing. Thanks for any help.

 

sideout2, how many miles on the truck. any engine mods? normal maintenance as per ford recommended intervals? no prior problems?

 

111,000 Mi. stock motor. no prior issues. reg oil change is about it. I am still tracking it down. I went and bought a manaual so I can have more info. Still if there are any ideas out there I would love to hear them.

 

sideout2, suppose a cat converter collapsed on inself and the interior of the cat is really stopped up. I think that in turn could create so much back pressure the engine cant run. Techs, any chance that is sideout2's problem.

 

that may be a possibility. The plugs did show it was running rich. They weree so worn thety were not getting a complete burn. 100,000 plat. plugs and all.

 

on your truck is it fairly easy to temporarily unhook the cat to see if that helps.

 

Any comments, sideout has my curiousity and i am wondeing what could cause his problem.

 

sideout2:

I'd check your EGR. Without any warning mine had taken a dump on me. The engine ran fine when i parked it then when i went to start it the next day it would turn over and try to run but it would die out. The EGR was the culprit. I'm curious to what your problem may be, let us know.

By the way, this happened on my 96 cougar 4.6L not my truck below.

-hooD

 

All
I disconnected the exhaust at the manifolds and it started up. I could rev it up with no hesitation. (sounded pretty cool) I did not run it to long as it is a little cold here(well 40 deg is cold in Texas.) and do not want to warp a valve. I supect the cats, but will take the EGR out as well while I have the pipe off. When it is all back together and running I will post more. Thanks for all the help so far.

 

sideout2, i am in sugarland near houston and i thought i heard you fire that sucker up. They sound great right out of the exhaust manifold.