Question about 1989 Ford Mustang
There is a reset switch in the trunk on the right side under the carpet or in the trunk on the back wall by the tail lights i had same problem found it and it was the fix i have the same car 89 5.0 trunk style hope this helps
Posted on Mar 28, 2009
The pump runs for 2 seconds when you turn the key on, then it shuts off. During cranking, it runs all the time.
here's 94 mustang circuit
Overview The fuel system for supplies the fuel injectors with clean fuel at a controlled pressure. The system is called Sequential Fuel Injection (SFI). The Powertrain Control Module (PCM) controls the fuel pump and monitors the fuel pump electrical circuit. The PCM also controls the duration of the on/off cycle providing correct timing for the injectors. If the injectors have been replaced, it is necessary to clear learned values contained in Keep Alive Memory (KAM) in the PCM. This can be done by disconnecting the battery or the PCM for five minutes. (Refer to Section 2,
Powertrain Control Module (PCM) Reset , for more information.)
Fuel System The fuel system consists of a fuel tank with reservoir, fuel pump assembly, fuel supply and return lines, fuel filter(s), pressure test point, fuel rail, fuel injector, and fuel pressure regulator, Figure 1.
When the ignition switch is in the on position, the EEC Power Relay is on. The EEC Power Relay, located in the CCRM, provides power to the PCM and the fuel pump relay coil, which is also inside the CCRM. Power for the fuel pump is supplied through a fuse link or high current fuse attached to the starter relay (battery side). Current flows through the Fuel Pump Relay and Inertia Fuel Shutoff (IFS) switch to the Fuel Pump. The IFS is a safety device designed to shut off the Fuel Pump in the event of a collision (Figure 2). If the IFS is tripped , it must be reset. Refer to the Owner Guide for instructions.
When the ignition switch is turned on, the Fuel Pump will operate. If the PCM does not receive PIP signals indicating that the engine is turning over, the Fuel Pump is shut off after one second. After the engine starts, the PCM will continue to operate the fuel pump unless PIP signals are not received, indicating the engine has stopped, or the IFS is tripped .
Posted on Feb 25, 2009
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Jun 10, 2015 | 1989 Ford Mustang
Feb 04, 2015 | Cars & Trucks
Jun 28, 2014 | 1999 GMC Jimmy
May 08, 2011 | Buick LeSabre Cars & Trucks
May 02, 2011 | 1989 Chrysler LeBaron
Aug 07, 2010 | 1989 Chevrolet Astro Cargo
Jul 16, 2010 | 1989 Oldsmobile Cutlass Ciera
Jul 16, 2009 | Chevrolet S 10 Cars & Trucks
418 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: