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Crazy Electrical Problems in 1990 5.0 LX

OK, I am having crazy electrical issues in my 1990 LX. I am sure everyone is familiar with the familiar whine of the fuel pump in these cars pressurizing. Well, when I have the key turned to accessory (just before start), the fuel pump constantly pressurizes, even while attempting to start it continues to pressurize. Also, the tach jumps around like a babboon, there is a strange beeping noise (like pulsing electicity) coming from something that I cant pinpoint under the hood and there is a clicking coming from behind the gauges.

I would think it was the Fuel pump relay if it were only the pump that was acting up. My other thought is an EEC Relay or MAYBE the recalled ignition switch. The reason I am suspecting the ignition switch is because it is almost like its acting like I am flipping the key back and forth from acc. to off.

Any help is greatly appreciated.

Thanks.

Cdm331

Reply to
cdm331
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should buzz 2-5 sec then stop, at pressure about 45-50 or so

not started yet but with just the key turned ? tach should not move at all,

Is the battery voltage low? like 10 V or below ?

Clicking almost has to be a relay ? replacing some of the relays on the fuse panel is quick, there is another relay I had to replace that was just up under the dash, Ford doesn't always put it in the same place, a bigger one, not sure what that was for.

Else break out he schematics, good luck

5.0 87 5.0 93 8#
Reply to
Dr Moria

Yes, it should buzz for two to five seconds and stop. But it doesn't stop, it just keeps buzzing. The battery is new and is testing fine. I changed the fuel pump relay and the EEC relay and neither made a difference. I think the relay under the dash you are talking about is the EEC. Its not the ignition module because it acts the same whether that is hooked up or not. The alternator is testing fine so the voltage regulator should be good (VR is on the Alt). And I know the tach is not supposed to move, but it does. I am not sure what else it could be and I dont want to start buying things to troubleshoot it. I was hoping someone on here would maybe have experienced something similar but everything that is wrong seems so wacky.

Thanks for your help.

Reply to
cdm331

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