relieving fuel pressure
07-30-2011, 01:21 PM
#1
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Year: 1996
Model: Cherokee
Engine: 4.0
relieving fuel pressure
about to change the fuel filter and the FSM mentions to relieve pressure from fuel system. I dont have a fuel pressure gauge/hose as they mention. what else can I do?
I read about pulling the fuel pump relay out and starting the jeep until it dies (also remove the fuel filler cap too) this okay to do? any negatives to doing this?
I read about pulling the fuel pump relay out and starting the jeep until it dies (also remove the fuel filler cap too) this okay to do? any negatives to doing this?
07-30-2011, 01:26 PM
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Year: 1998
Model: Cherokee
Engine: 4.0HO
The FSM does have those steps along with some others like putting power directly to one injector from the battery. I can't remember the steps in order but what you mentioned is part of the process. Also disconnecting the fuel line on the fuel rail.
07-30-2011, 01:50 PM
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
If you want to put power directly to one injector the easy way go to the parts store and grab an injector harness (ounce that connects to the injector) hook it up and use a 9 volt battery to activate the injector.
07-30-2011, 02:07 PM
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Year: 1990
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I'm lucky... I have a pressure relief on the rail. Actually you should too. Looks like the hook up for a bicycle pump. It is also where you hook up the fuel pressure gauge.
07-30-2011, 02:12 PM
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07-30-2011, 02:19 PM
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07-30-2011, 08:11 PM
#9
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Year: 1998
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Engine: 4.0L
If you remove the fuel pump relay and try to start the vehicle you will remove almost all of the fuel system pressure... As others have suggested you can push the center pin on the fuel rail service port to relieve any residual pressure... The amount of fuel coming from the service port will be minimal, but when you go to replace the fuel filter there will be several ounces that will come from the fuel lines and the existing filter.... Just have some rags and a small bucket handy....
07-31-2011, 12:05 AM
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Year: 1990
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I'm old school and I grew up on a ranch. I still start a gas siphon wit my mouth. I'm not afraid to weld in shorts and flip flops. And I don't use a jack to take out a transmission.
07-31-2011, 12:51 AM
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Year: 1994
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Yeah, but I didn't need cancer at an early age. I don't wear safety glasses EVER and a lot of times I forget to disconnect the battery. Everything I do is just to make it easier on me. Like using a 2-1/2" bolt to pop a front axle hub off instead of a bfh. Easier, smarter, cheaper, less bloody.