Ford Repair: IDLE ON FORD EXPLORER, fuel pressure gauge, fuel pressure regulator

Question
Clay,
I own a 94 ford explorer xlt. Since i purchased it, it has always idled up and down usually between 500 and 1100 rpm. I drove the vehicle for several months after i purchased it to make sure it was dependable for my daughter. Now the truck is continuing to idle up and down and at stop signs are even while i'm driving it will go dead. Sometimes i must let it sit for a while (5 minutes to 4 hours) before i can crank it. I contacted the man i bought it from and ask him if he ever had any problems with the truck and the only problem he had was with the idle and he said it was some sort of sensor that had to be replaced and it cost him around 80 dollars. Unfortunatly i have moved to Dallas and lost his number and my daughter has a truck that will crank sometimes and make it out of the drive way and die are it will not crank at all. If you have any suggestions i would love to hear them this is becoming very frustrating. Thank you in advance for your service and this site.

Chris Damants

Answer
Chris, I know you'd like to have a definitive answer as to what is causing your problem... but I'm afraid there are many possible causes.
If the cause is a sensor that is out-of-range, I would expect you to have a 'check engine' warning lamp on at times.  That would be the place to start - a diagnostic code that is stored would tell you what system needs to be investigated.
You could have a sticking EGR (exhaust gas recirculation)  valve, or a sticking IAC (idle air control) valve, or a weak fuel pump, or faulty fuel pressure regulator, or a vacuum leak, or .... the list goes on and on.
Unless you have a scan tool and a fuel pressure gauge that will adapt to the fuel rail, you probably need to find a shop that you can trust to perform the diagnostics... then decide if the repair is something you want to tackle.
Hope this helps...
Clay