Hi everybody i am having an issue with a 1990 ford truck 5.0L
it was running fine and then wouldnt run again will turn over and fire but wont run i was wondering about the coolant temperature sensor i changed the fuel pump it wasnt working and fuel pressure regulator fuel pressure is 35psi

 

Did you pull codes?

 

no codes at all had a scan tool on it the truck was running fine but it had trouble starting the first time it ran but when running ran good good idle now it will crank good and fire but just wont run

 

Make sure you have spark. Not just coil power and spark. Had this prob was a loose ground on fender solenoid, well next to it. I had power and everything to solenoid/ distributor key on but when engine turned over starter stole ignition ground. Causeing no spark on start up

 

You must be able to retrieve codes-first step in no-start.

When I bought my 1990 f250 4.9 in 2008 I replaced VSS, TPS, coil, solenoid, ACT & ECT sensors, IAC, TFI, fuel pressure regulator, both FDM,s and tanks, ECM & fuel pump relays, and still had no start.
Discovered spraying carb cleaner into intake tube would get it started but had terrible performance (no power, backfire, horrible mpg, & just general disappointment/frustration).

I finally discovered FTE and quickly learned "hiccup" was operating in "failure mode".
Many many folks had repeatedly told me ". . .the ECM's never go bad in these trucks,"---pft, whatever!
I did not/have not regretted replacing all those items (would have eventually anyway) on a 18 year old truck that sat in the weeds behind a barn for 8years, with 100,000+ miles (broken speedo too) but I was very frustrated that it continuously would not get out of its own way and would not start without opening hood!

Shared all that to make this point, RETRIEVE CODES FIRST. If you cannot, go no further with random sensor/actuator replacement, save your cash and sanity.

Pull ECM, (behind drives kick panel) look inside for damage ie leaky capacitors and/or stains on board.
Mine had classic failure evidence. After trip to Bumper to Bumper I finally replaced the ECM that "never goes bad" and voile, truck runs like a million dollars!
Still drive this truck with a smile because I won!
Let us know what you discover, good luck.