Relieving Fuel Pressure? 91 4.0L Ranger


srisitt

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How do you release the fuel pressure on a 91 4.0L? In my chilton manual it says I need a special tool to release the valve at the engine block, but some things I read online say to disconnect the fuel pump relay via a connector underneath the fuse box. I looked inside the fuse box and found a 30A fuse labeled for the fuel relay, if I disconnect this will it relieve fuel pressure?
 


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Disconnecting that and cranking would certainly do it. You could also wrap a rag around the shrader valve on the fuel rail (looks like a tire valve stem) and press the valve in so any pressurized fuel soaks into the rag.
 

rusty ol ranger

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I just yank the relay/fuse, fire it up, let it run till it stalls, then get to work.
 

srisitt

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Disconnecting that and cranking would certainly do it. You could also wrap a rag around the shrader valve on the fuel rail (looks like a tire valve stem) and press the valve in so any pressurized fuel soaks into the rag.
Interesting, is there an additional relay underneath the fuse box then or is it just the fuse on the 91? I heard there’s a green relay that snaps to a connecter under there
 

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I'm surprised the relay isn't visible from the top of the fuse/relay box.
 

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I'm surprised the relay isn't visible from the top of the fuse/relay box.
Yeah, in a video I saw it’s underneath, you have to remove the fuse box to get to it. But the fuel relay fuse is right in the box and labeled on the lid.
 

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That ought to work as well.
 

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Or if youre really feelin froggy you can trip/unplug the inertia switch.
 

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The inertia switch isn't really designed to be used more than once.
 

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Then why did they put a reset button on it?
Same reason they put "wet paint" signs on something that has just been painted. " To make people touch it"
 

rusty ol ranger

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The inertia switch isn't really designed to be used more than once.
Either is toilet paper. But there are those amongst us.
 

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rusty ol ranger

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To get it away from an accident.
The purpose of the inertia switch is to kill the pump in case of an accident, in order to prevent fuel spillage and/or fire.

So, since they put a reset on it in order to drive it from an accident, doesnt it kind of defeat the purpose if fuel really was leaking?
 


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