i've been having problems with my '91 f250 5.8L.
most of time it will crank but won't start. i hear fuel pump running and usually won't stop when engine doesn't start. was told maybe fuel press regulator, but not sure where it is, and also was told that if it's connected to vacuum to just pull hose of and if diaphragm is bad fuel will come out.
don't know where it is first of all and second if it's not that what else.
have replaced fuel filter and fuel pump relay...please help.
i am a newbee to this site and was really hoping for some help.
thanks,
forof250

 

i had this on the wrong post to begin with and thanks to RIKIL and
real ford man (?) for helping with new post as well as a couple ideas already.
but any other help would be greatly appreciated.
forof250

 

Really a bad time when they don't run. You need to determine if you have spark, use a spark checker, or use the coil wire, or try spraying a little starting fluid in the air intake tube. Just a little bit of a spray, if she fires, report back here for some other ideas for checking the fuel system, or electrical, if she didn't fire...are you sure that the pump stays running and not the heater fan or something else

 

thanks for the reply, yes it does have spark and yes i hear the fuel pump running, but it doesn't seem to stop, i can hear the difference when i select rear fuel tank and front tank so i know the fuel pump is running. i thought i'd try to change the fuel pump regulator, but i think you need special tools to replace it. i could get a 4mm allen wrench on one of the screws, but forget the others! will have to go into town to get some starting fluid. i actually thought of that and wonder if i could just punch a hole in the top hose to the throttle body so i could spray the starting fluid into the body and close hole with screw?

 

no... don't punch an hole in it... just take it off and shoot the starting fluid strait into the TB.

 

Do not punch a hole ...just spray where the air goes in the tube, it really won't need but a bit of spray, even though you are far away from the intake body.. Pull the vacuum hose off the fuel regulator, just to see if any fuel is present there, there should be none.

 

Have you had your computer checked? If its fried, then you'll never get it started. And something else you might check is your ignition control module if it has one. It can cause your spark signals to goof.

 

thanks you all, i might be able to some work on it today.....but looks like i'll be going away for a couple weeks, going to pa for a little hunting but will be starting again when i get back. i can't tell you enough how much i appreciate
all the help i've been getting from you guys on this forum too bad i didn't find this site earlier..... thought i got a really good deal on this truck, a '91 but onlly has 41k miles and got it for $500
thanks again fellas,
forof250

 

ended up postponing my pa trip so worked on the truck, i did spray starting fluid in top air port on throttle body and it did end up starting, sputtered a little at first but then seemed to run ok.
seems once it starts running it can get enough fuel to run.
would that be the fuel pressure regulator?
forof250