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'96 Merc Sable-fuel related

'96 Merc Sable. Possible fuel or Fuel Pump related problem?

Aquired vehicle after it sat for aprox 2 years. Previous owner did not want to get engine mouunts replaced-this is not my problem. While waiting to get title from owner, I removed old fuel from tank, added new fuel and Sea Foam. It fired right up, let it warm up, checked and topped off all fuilds. Has started right up at least two more times since.

Three weeks later: Would not run, it will crank over and over and will run down battery. Recharged battery and followed Chilton manual-checked fuses and inertia fuel shut off switch-ok, tried to listen down fuel fill line for whirling sound of pump-can not hear it. Vehicle has intergrated Fuel Pump relay located in CCRM. Used jumper wire to bypass CCRM and still could not hear Pump running when key tuned on. Replaced fuel filter. Want to check pump resistance with ohm meter but can not locate wire connector or the correct wires in chilton manual. Wiring charts in manual are not the same as what I find in vehicle.

Whatever you do, do not use a Haynes or Chiltons manual as a reference for wiring diagrams. These manuals are dead wrong and even omit components in the electrical circuit.

With that said, take a rubber mallet and give the bottom of the gas tank a couple of good whacks. This sometimes frees up a sticking fuel pump to get it to run again.

Tester

Is there more to the story that suggests that you lost fuel pressure rather than spark?

Have you checked for fuel pressure? The engine does not need to be running to do this, just 12VDC applied to the pump. Or hook up the gage and try starting it…the line should pressurize.

Have you checked for spark?

Thanks. I have tried the Mallet trick a couple times with no change. I also have tested the fuel pressure with a guage and have not recieved any pressure showing with the key in run.
I hear a relay click in the CCRM box when turning key to run and still not hearing any whirling sound at fill tube at fuel tank. The chilton manual instructs to check for voltage at pump wire connection. I still can not figure out which wire is which and how to test the resistance of pump itself before dropping tank and replacing. I also have spark at plug wire. I believe I must figure out if it is the relay or pump itself before ‘shot-gunning’ I have not researched Mitchell yet inorder to access better wiring diagrams.

I am not sure if you saw my above response to Tester or not. I have checked for spark and have got it. Thanks for any help…

I think that you almost certainly have a bad fuel pump. Ford puts (or used to, at least) high amperage fuses in a separate fuse box under the hood. You checked the fuses there, correct?

Yes, Ford has a large 20 amp fuse that is for the fuel pump/relay circuit system and it is still ok. I have been leaning towards the pump as bad, but have not been been able to test it correctly. Thanks for the advice.

Try the wiring diagram Fig. 8, for your car, at www.autozone.com. You may have to register to search the different types of information. Auto Zone just re-formatted their Web site, today. Click: 1. http://www.autozone.com ; 2. Register your vehicle. 3. Click Repair Info. 4. Vehicle Repair Guides. 5. Chassis Electrical. 6. Wiring Diagrams. 7. Scroll down and select Fig.
When you try to view the figure, you will need to go to your pc View, down to Zoom, over to Zoom In for 6 clicks of enlargement. You may, also, need to View Full Screen F11.

[We need to tell Auto Zone Web site management about this difficulty.]

Here are the checks for the CCRM (Constant Control Relay Module), if your car has one: http://www.4s.com/FourSeasons/tech_tips/tech_tips_english/AB354_Testing_IRCM_CCRM_02.pdf