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Discussion Starter #1
So my friend has an 88 and did an engine swap with a 95 351 with harness and ecu and since he did the swap it has been acting like its out of gas unless he sprays starter fluid (i know bad idea I tried telling him) he replied both pumps, filter, checked vacuum lines and fuel pressure regulator. Any in site would be great. Thanks guys
 

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An 88, would have had two fuel pumps, low pressure high volume in the tank, and high pressure on the rail.
A 95 would have had a single high pressure pump in the tank.

Are both pumps getting power?
 

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yo,

Testing & Operational Sequence; First, do a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19. Look Codes up in my broncolinks.com site using the new Search function if in a hurry today. And Post em here according to KOEO & KOER. Does starter turn over well? or is it hesitant to turn over the engine? Have starting & charging sys checked for free at a local parts store anyway. When turning ignition key, is it free to turn and engage well in start, run, accessory positions Guesses; EEC Power & fuel pump relays often go bad; Eziest checks first;
92-96 EEC power & fuel pump relays are in underhood in Power Distribution Box on driver's side next to air box. Pull the EEC and FP relays and inspect & test. Expect corrosion in sockets and on relay contacts. Test your relays by applying 12 V across the small terminals, listen for the click and check continuity across the large terminals. This will rule out the relays themselves being a problem.
SWap Horn Relay for FP Relay; try to start
Pump Testing & Diagram at the Diagnostic Link Connector in 84-95; Connect FP Relay to any ground to force the fuel pump(s) on when the key is in RUN...87-95 (black or gray) located under L hood hinge under EEC TEST cover. (WPT-743 & WPT-352. Operational Sequence: When the ignition is switched to the ON position, it turns the EEC Power Relay on. The EEC Power Relay provides power to the EEC-IV processor and the control side of the fuel pump relay. Power for the fuel pump is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flow is through the fuel pump relay and Inertia Fuel Shutoff (IFS) switch to the fuel pump. The IFS switch is a safety device used to shut off the fuel pump in the event of a collision. If the IFS switch is "tripped," it must be reset by depressing the white or red button on the top of the switch. The fuel pump relay is controlled by the EEC-IV . When the ignition switch is turned to the ON position, the fuel pump will operate. If the ignition switch is not turned to the START position, the EEC-IV will shut the fuel pump off after approximately one second. The PCM will operate the fuel pump when the ignition is in the START position to provide fuel while cranking.After the engine starts, the PCM will continue to operate the fuel pump unless the engine stops, engine speed drops below 120 rpm, or the IFS switch is "tripped." Note: Grounding the FP lead at the DLC will allow the pump to run continuously with the ignition switch on. MIESK5 NOTE; from Ford EVTM; The Control Module (PCM) runs the pump for one second when it receives an ignition- on signal. It also runs the pump as long as it receives a PIP signal from the Hall-effect devices (inside the Distributor), it continues pump operation even after the key is released from START. If the PIP signals fall below 120RPM, the control module cuts off the signal to the fuel pump relay. The pump will also run when the terminals of the fuel pump test connector are jumped. the Control module signals the pump when it receives a CRANK signal, and when the Control module gets PIP signals that the engine is running. the pump does not run if the PIP indicates the engine is not running even with ignition ON {except for that first one second}.
Source: by Ford via miesk5 at Ford Bronco Zone Forums


Wiring Diagram in a 95
Source: by SeattleFSB (Seattle FSB) at http://www.supermotors.net/registry/media/851796

Testing & Diagram at the Diagnostic Link Connector in 84-95; "...Connect FP Relay to any ground to force the fuel pump(s) on when the key is in RUN..." MIESK5 NOTE; from Ford EVTM; The Control Module (PCM) runs the pump{s} for one second when it receives an ignition- on signal. It also runs the pumps as long as it receives a PIP signal from the Hall-effect devices, it continues pump operation even after the key is released from START. If the PIP signals fall below 120RPM, the control module cuts off the signal to the fuel pump relay or the integrated relay control module. The pump will also run when the terminals of the fuel pump test connector are jumped. the Control module signals the pump when it receives a CRANK signal, and when the Control module gets PIP signals that the engine is running. the pump does not run if the PIP indicates the engine is not running even with ignition ON {except for that first one second}.
Source: by Steve83 (Steve, That dirty old truck) at http://www.supermotors.net/registry/media/245234


No Start 2: Checking for Fuel.
Checking for Fuel involves two separate tests. One is to check that the Fuel Pump is functioning and supplying the correct amount of pressure.

The other test is making sure that the PCM is activating the Fuel Injectors. This can easily be accomplished by using a Noid Light to check for these On/Off activation pulses the PCM sends to the Injectors.

CASE 1: Fuel Pressure is at specification This result confirms that the Fuel Pump is OK and doing its part. Also, this test result confirms that the following components are OK too:

•Fuel Pump Fuse.
•Fuel Pump Relay.
•Fuel Pump Inertia Switch.
And so, there's no need to spend time testing them or money replacing them.

CASE 2: Fuel Pressure is not present This usually means that the Pump has failed, but not always. I would recommend testing/checking the following before condemning the Fuel Pump:

•The Fuel Pump Inertia Switch.
◦Checking to see if the Inertia Switch has tripped is very important, before condemning the Fuel Pump.
◦If the Inertia Switch has been tripped, the Fuel Pump will not power up... so checking it and resetting it (if it has tripped) will save you from replacing a good Fuel Pump.
•Fuel Pump Power Circuit.
◦The other very important thing to do, before condemning the Fuel Pump is to make sure it's getting power.
◦This can be done by tapping into the Fuel Pump's power circuit with a Multimeter.
◦Once you're tapped in, have a helper crank the Engine while you observe your Multimeter in Volts DC mode. If Voltage is present (12 Volts), then you have confirmed that the Fuel Pump Fuse, Fuel Pump Relay and Inertia Switch are working perfectly.
◦Confirming power to the Fuel Pump (with a Multimeter) also verifies that the Fuel Pump has failed and needs to be replaced.
◦If no Voltage is present, as your helper cranks the Engine, then the cause of No Fuel Condition is due to either a BAD Fuse, Fuel Pump Relay, or Inertia Switch.

read more
 

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Discussion Starter #5
I'll have him check up on this stuff and get back to you guys with his finding thanks for info and tips guys
 
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