No Fuel at rail

I just got a 91 bronco when i bought it i was told that a 94 f150 motor was installed in it. the problem that i am having is their is fuel making it to the FPR but it is not passing that point i replaced the FPR thinking that it would fix it but it didnt, i also checked the lines and they don't look crossed and the are two different sizes. Could a vacum leek causing the regulator to not open i dont know what else to try and i really dont want to spent 180 dollars on a fuel pump if i dont need one

it is my understanding that the fpr is at the end of the fuel rail and controls how much fuel gets sent through the return line to the tank, if there is fuel at the fpr then there is fuel at your injectors, a lack of vacuum would cause the fuel pressure at the injectors to go up.

however we all need more information from you so we can help.

What size of motor is it, was it running when you bought it, or has it not been running since installing the new engine. and why was the original engine replaced.

yo,

Pull the red vacuum line & check for gasoline...There shouldn't even be the ODOR of gas in it

W/engine idling, carefully disconnect the vacuum line going to the fuel pressure regulator. Fuel pressure typically jumps to 40 PSI ± 3 PSI (4.9L typically is 15 PSI higher).

A high pressure fuel tester must be connected to the fuel Schrader valve on the fuel rail.

First relieve fuel system pressure, then attach the tester. Next, turn the key on (engine off) to prime the fuel system. There should be about 36-42PSI of pressure.

Fuel Pressure During KOER Self Test for 92; 4.9 (45-60 PSI), 5.0 (30-45 PSI), 5.8 (30-45 PSI) & 7.5 (30-45 PSI);

Start the engine. The pressure at idle should remain within the same range. Rev the engine a few times to ensure fuel pressure remains constant.

Excess pressure usually determines a faulty FPR. Too little pressure could be the FPR, fuel filter, fuel pump(s) or relay, or a leak.

Eng vacuum affects fuel pressure; ck for vacuum leaks and get a vac gauge;

Mount it inside and use to also help increase MPG by keeping needle in Green Zone (steady speed and acceleration)

"I have a vacuum gauge mounted right in the dash of my truck. I use it to also help determine the load my engine is under while driving, and to estimate fuel economy..." by unknown

Vacuum Leak Test; On an idling engine check for vacuum leaks using a mechanic's stethoscope with the probe removed, or a ~3' garden hose section. Don't spray flammables on a running engine. MIESK5 NOTE; Also check: vacuum hoses; intake manifold gasket & throttle body; PCV line; vacuum reservoirs: EGR Sys Vacuum Tank & 2ndry air (coffee can); AC, heater, defroster, vent control ckt & vacuum tank (plastic ball type), under dash & lines to heat/blend/etc. doors; power brake booster; cruise control ckt, etc.... where applicable; BEWARE OF BELTS/PULLEYS, FAN AND HOT ENGINE

Vacuum Gauge Diagnosis - BEST!; Normal engine; Steady gauge 18"-20" at all speeds..." READ MUCH MORE

Source: by Craig U at http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm

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for more info on FPR, & System see;

Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; & Ford Fuel Injection and Electronic Engine Control: How to Understand, Service, and Modify All Ford-Lincoln-Mercury Cars and Light Trucks, 1980 to 1987 by Charles Probst

avail @ BARNES & NOBLE, AMAZON, E BAY, ETC.

yo, UPDATE; This is by FORD for a 94 Bronco; in da PCED

The Fuel Pressure Regulator (Figure 3) is attached to the fuel supply manifold assembly downstream of the fuel injectors. It regulates the fuel pressure supplied to the injectors. The regulator is a diaphragm-operated relief valve. One side of the diaphragm senses fuel pressure and the other side is connected to the intake manifold vacuum. Nominal fuel pressure is established by a spring preload applied to the diaphragm. Balancing one side of the diaphragm with manifold vacuum maintains a constant fuel pressure drop across the injectors. Fuel in excess of that used by the engine is bypassed through the regulator and returns to the fuel tank.

A pressure test point with a Schrader fitting is in the engine fuel rail to relieve pressure in the fuel system and to measure the injector supply pressure for service and diagnostic work. Refer to Caution and Warning.

Fuel Injector Connector Color & Flow Rate Number, System Schematic & Depictions in a 94 (NOT FOR INJECTOR INTERCHANGEABILITY); "...5.0 & 5.8 Truck; Part Number F2TE-AA; Connector Color, Gold; Resistance Ohms, 11-18; Flow Rate #/Hr 19; The Fuel Injector (Figure 5) is a solenoid operated valve that meters fuel flow to the engine. The injector is opened and closed a constant number of times per crank revolution. The amount of fuel is controlled by the length of time it is held open. The injector is normally closed. It is operated by 12V VPWR from the EEC-IV Power Relay and the ground signal is controlled by the Powertrain Control Module (PCM); Note: Do not apply battery voltage directly to the injector electrical connector terminals. The solenoid may be damaged internally in a matter of seconds...."

thanks for the help after reading your posts i looked at the fuel lines and some one had them back words down by the filter the bronco is running now thanks alot

yo,

WOW..

thanks for getting back w/that!!!

I'll put that in my List of Previous Owner/Shop ....ya know...

Never know what we'll find, huh?

Be well!