Fuel pumps wont come on

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Carlisle 2020
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Fuel pumps wont come on

Post by mike701324 » Wed Jul 08, 2020 7:39 pm

Bought a 1989 merkur xr4ti non running. Owner said it was running last fall but could not get it running after winter. Checked out the inertia switch its good works well and connectios are good. Chassis ground in back good as well. Just replaced the old fuel pump as couple days ago and was reading 0v to the pump. Checked the relay 12v is reaching the relay slot. But i see nothing at the fuel pump fuse.. Couple other weird things the blinkers and horn worked fine. Till today. Lol. Is there any way to hot wire a switch to turn the pumps on? Thnks in advance.

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Re: Fuel pumps wont come on

Post by hbar » Wed Jul 08, 2020 11:46 pm

I would run a hot jumper wire to the fuse and see what happens. If the pump comes on then you know the problem is before the fuse box.
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87 Merkur XR4ti, 5 spd, White, Summer driver
2014 Ford Focus SE, ECU tuner.

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Re: Fuel pumps wont come on

Post by merkurdriver » Thu Jul 09, 2020 3:37 am

If you have 12v at the pump relay in the fuse box I would check the ECU relay under the glove box next to the computer.
(I keep a spare of this relay and TFI module in the glovebox of every XR.)

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Re: Fuel pumps wont come on

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Re: Fuel pumps wont come on

Post by Bob Weir » Thu Jul 09, 2020 10:24 am


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Re: Fuel pumps wont come on

Post by andyofcolumbusmerkur » Thu Jul 09, 2020 12:38 pm

Cool. Sounds like you got a very rare car and I bet for a bargain non-running and all. Do you have the digital shop manual on pdf? You want that for sure. You may want to think about putting in a single Walbro pump instead of the dual pump setup, with new wiring filters etc. Maybe you could take back the pump you bought if it doesn't smell like fuel. The out of tank high pressure pump can fail and the wiring is exposed and can cause problems. A parts store pump may not be very high quality. I think the fuel system should be 100 before anything else is done like upping the boost or putting in a different ecm. If your going completely stock you can get oem parts though the vendors here.

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Re: Fuel pumps wont come on

Post by zxr250cc » Sun Jul 12, 2020 11:22 am

Hi all,

I keep returning to this looking for more info and keep wondering if mice are the problem. Nibble, nibble, nibble...

1986 XR4Ti Mineral Blue Metallic

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