New fuel pump not working. HELP!!!

[dirttrackSHO]

I need help. My '89 will not get fuel to the engine. There were several indications that it was the fuel pump. That has been replaced, but it still will not pump fuel. When you turn the key on you can not here the pump kick on.

Someone told me that it could be the Integrated Computer (little black box on the top of the radiator). Apparently this box contains the fuel pump relay. However, I have disconnected this box and put it on my '91 and the car runs perfect.

Does anyone have any ideas on what could make the fuel pump not work? (We also replaced the inertia switch.) shrug

 

[Mr Anonymous]

Well, it sounds like you eliminated the CCRM, so the next step in my mind would be to verify that power is getting to the fuel pump. Check first that power gets to the inertia switch first, and then check between the inertia switch and the fuel pump. Do you have a multimeter to help you with this?

I'm also thinking there might be a fuse for the fuel pump in the distribution box under the hood -- check for that too.

 

[projectSHO89]

I posted a complete fuel pump dircuit dignostic procedure right after Christmas.

Go here and happy hunting (otherwise, just take a few guesses and see if you get lucky)(check/reset the inertial switch before going too much farther): http://www.shoforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=17;t=004925#000001

Steve

 

[dirttrackSHO]

Someone has told me that you are not supposed to be able to hear the fuel pump engage when you the ignition into the run position. Is this true?

When the car would run (sometimes it would sometimes it wouldn't) you could hear the pump engage. Then one day you couldn't. The new one doesn't make any noise.

I am getting power to and from the interia switch.

I will do the rest of the diagnostic procedure as soon as I can get back over there.

Thank you.

 

[LaTechSHO]

try using jumper wires to jump the connector to the inertia switch.... once upon a time in a POS T-Bird i used to own the same thing happened....

as it turned out the inertia switch WAS bad, but allowed for 12V and hardly ANY amps to pass through to the pump.... it was a last resort, but turned into the miracle cure...

give it a shot....

Louis

 

[projectSHO89]

Louis,

if the pump was connected, then the voltage should have been dropped across the switch due to defective contacts.

The only way that you could have a switch which was defective and still measured 12 V on both sides would be if there was no load on the output of the switch.

Been fixing electronics for over 25 years, that's a simple implementation of Ohm's Law.


I can hear the pump on every Ford I own or have ever owned. Some are louder than others, even new ones from Ford's parts system are not quiet.

If you do indeed have 12 V on both sides of the inertial switch, you swill have an open circuit, either in the wiring to the pump, the pump, or the ground for the pump power.

Steve

<small>[ February 21, 2003, 10:58 PM: Message edited by: projectSHO89 ]</small>

 

[dirttrackSHO]

Can I just eliminate the inertia switch by wiring the wires together?

Thanks for all your help.

 

[projectSHO89]

Yes