I recently bought a 89 f250 super cab, long bed with the 460 engine and dual tanks and drove it home. The engine was running good and strong. After replacing some front suspension components, I tried to start the truck with not luck. The engine cranks, but no fuel pressure. I tried the Operational checks in Haines manual Chapter 4-8, but no luck there either. I pulled the high pressure pump and it is good. Inertia switch is good.I reinstalled and tried to start again. When I turn to key to run, I can here and feel the EEC relay close (brown relay), but nothing with the fuel pump relay (green relay). I pull the fuel pump relay and put 12v across the terminals while checking for continuity, the relay seems good. If I bypass the fuel pump relay with key in run position all three pumps cycle, but engine still will not start.
I have not had a chance to check for spark or anyother electrical components. Is there a sensor that would prevent the fuel pumps from running?

This is my first Ford, but I am use to working on vehicles from owning Chrylser products.

Any help would be greatly apreciated before my wife beheads me for buying another yard planter!

Also anyone know of a good cleaner to get the oxidation and corrosion out off of electrical connectors?

Thanks,
smose

 

If your truck has a carb, then you have the fuel pump relay that is controlled by the starter relay when starting the truck, and by a oil pressure switch when the truck runs. Look in the haynes manual in the back, and they have a circuit called "hot fuel handling"(if your truck has a carb).

 

It has the Multi-port fuel injected 460. I am going to replace the relays for the eec and fuel pump tonight. The start up mode test failed and Grounding the fuel pump terminal on the Data link connector failed to power up the fuel pumps. After installing hte new relays I am going to preform the circuit checks per section 15 chapter 4 of Haynes manual. Hopefully it is something simple I over looked.

Smose
1989 f250 trailer special

 

Thursday after work I began to trouble shoot the wiring starting from the wiring for the EEC relay and the Fuel pump relay. It turned out to be two bad wire terminals, one on each relay and a bad EEC relay. Took me about 20 minutes to figure it out after much time spent studying the wiring diagrams at lunch that day. I had power going into the EEC relay but not coming out, fixed that. Than I had power to fuel pump relay but none coming out, fixed that. Turned key, pumps ran and the truck fired right up! The engine runs even better than when I purchased it a month ago today. Must not have been getting full current to all of the electronic systems. It passed E-check (emissions testing in OH) with flying colors. Got her registered and on the road yesterday. Now I just need to find some good tires and she is ready to pull.

Smose