2000 ford 7.3 problem

[javrey]

have a 2000 ford 7.3 when hooked to a load wont go over 40mph. tryed new fuel filter and sucked fuel out and tryed again same problem. had dealer put on computer and they replaced #8 injector and everything checked fine. hooked trailer up again and same problem. went back and said nothing wrong they test drove and then changed oil still same problem. they said it could be one of 3 sensors but computer showing no problem. also with out load if you go up to 70mph it will acted up and go 40mph til you shut off restart. thanks

[stumpuller454]

what does it do at 70mph? just bog out till 40mph? sounds electrical or sensor related, could be a bad wire that is cutting out during high load (& amp draw) situations, i had the computer replaced on my 01 7.3, you would be driving along and it would "cut out" for half a second and go again, was kinda worrying, they are gonna have to hook up the computer and ride along with you and your trailer, see what signal cuts out, might be time consuming ( and wallet biting) but thats what it sounds liketo me.

[mrjohnwayne]

does it blow a lot of black smoke when hooked to a load? I would start by checking for boost leaks.. Sounds like with a load it is not building enough boost to overcome the load.. Start at the turbo and check all connections looking for loose clamps or holes in the boots.

just in case check out this picture. Where the blue tubes are start there and follow them to the intercooler by the radiator.


Hope this helps.

[stumpuller454]

THATS THE CLEANEST 7.3 IVE EVER SEEN!!! F`IN EH MAN! thats pride right there!!

[03chevy]

yeah stump that's something that people don't think about when they wash their rides cleaning under the hood. when i go to a self car wash i get a lot of looks when i wash my truck because i go as far as laying down and washing the undercarriage

[tjzz4]

If they replaced an injector they must be thinking it`s dropping a cylinder. the under valve cover harness which is intergal to the gasket is notorious for circuit problems.

[mrjohnwayne]

Originally Posted by stumpuller454

THATS THE CLEANEST 7.3 IVE EVER SEEN!!! F`IN EH MAN! thats pride right there!!

Thanks man, but that isn't clean.... Well kinda

Originally Posted by tjzz4

If they replaced an injector they must be thinking it`s dropping a cylinder. the under valve cover harness which is intergal to the gasket is notorious for circuit problems.

You are correct, but since the #8 injector is different from the other 7 (it is a long lead injector to compensate for the lack of fuel it receives, because it is at the end of the factory fuel circut) they do have a common failure rate.

Usually if it is the UVC (under valve cover harness) it will mess with both injectors (6 and 8, or 2-4 etc.. depending on what harness.)

[stumpuller454]

I guess i`m used to diggin under those 7.3s to see em, they seem to absorb and hold dirt very well, and nobody cares to clean em!

[javrey]

thanks for the info on truck ,after 2 trips back to shop and them calling some ford techs back east they dropped tank and blow out fuel lines and changed pump intank and screens and said fuel pump had low pressure thanks