I bought a 1995 f150 with a blown 5.0, so I found a low mileage 5.0 out of a 1990 F150. Install bolted right up, engine will run on starting fluid in the throttle body, but wont on gas. I have changed the fuel filter and I can hear the pump running in the tank. I am thinking fuel pressure regulator or pump in tank is weak and not supplying the psi needed. O'rileys autoparts online has two different part numbers for a fuel pressure regualtors for a 1990 and 1995 5.0 302. thanks

 

Are you saying the fuel pumps are running all the time the key is on?

 

What he said^^

 

Yes, I can hear the fuel pump running in tank, and pulled the gas line off of the fuel rail and have gas there, but none on the return side

 

when I turn on the key I can hear the pump then if I dont crank it the pump will stop after a few seconds.

 

I guess the next step would be to put a noid light on one of the injector plugs, crank the engine and see if it flashes.
I do not think you need a fuel pump or regulator at this point.

 

what is a noid light?

 

It is a little light that you plug into the plug you took off an injector.
Then when you crank the engine it will tell you if the computer is grounding that injector (it lights up er flashes).



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k thanks do you know where to get one?

 

never mind found them on ebay. thanks again

 

You can rent them free at most auto part stores.

 

I have a qusetion for the original poster.......I have a 1995 150 with a bad 5.0 engine. I have found a 1990 F250 with a good 5.0. Is this a direct swap? Do I have to swap over all the 1995 fuel system/intake, etc. for the '95 sensors to hook up? Any insight into this project is appreciated.

Many Thanks,

Highway 101

 

so, far I have only had to replace a plug pigtail with one I matched up at o'rielys autoparts. I am not finished with the swap yet. I havent had the time since its been so hot in texas this year.

 

the pigtail on the crank sensor

 

This is a direct swap with 1 exception, on a '90 truck the TFI ignition module was mounted on the distributor but by '95 it had been moved to the fender, so you have to modify one of a couple things to get a complete ignition system or the motor won't run.. hint hint. The possible solutions are..

A Better) Install the '95 distributor in the '90 motor after changing the distributor drive gear. The '95 motor has a steel roller cam while the '90 has a cast flat tappet and the distributor gears have to match or one of those parts won't last very long.

B Worse) Use the '90 distributor and modify the wiring harness to reach the distributor mounted TFI module.