How to check sniper EFI fuel pressure
#11
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From: WI
original sniper just run from the return port to the tank. on the new sniper two there is no internal regulator so you have to run a regulator on the return hose. go buy a mech fuel pressure gauge and hook it an unused port on the water fuel separator and run a hose up to the dash area. it can be the small plastic hose as it is only temporary.
#12
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From: Murrayville Georgia
when you say it has full throttle movement is the screen showing 100% TPS? does the screen show the same 3800 rpm as the tach. also is this a new install? does it have an anti siphon valve? you may have a fuel hose failing between the tank and pump or the anti siphon is too much restriction for the pump. if all else fails get a 5 gal jug and run a new hose from it to the first filter to take the tank out of the equation and see what happens. this all assumes the fuel pressure drops off above 3500 rpm.
#13
What I posted is generally how most efi's are rigged. The external regulator bleeds off the excess fuel pressure into the return line.
Your regulator must be internal and close to the fuel return line connection.
#14
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From: Murrayville Georgia
I don't know anything specific about the Sniper system and didn't know about it having an internal regulator.
What I posted is generally how most efi's are rigged. The external regulator bleeds off the excess fuel pressure into the return line.
Your regulator must be internal and close to the fuel return line connection.
What I posted is generally how most efi's are rigged. The external regulator bleeds off the excess fuel pressure into the return line.
Your regulator must be internal and close to the fuel return line connection.
#15
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From: On A Dirt Floor
Or a gopro available ?
Edit in: you pull your spark plugs to see if anything is being eatin’ ?
#16
If you put a fuel pressure tester on it and it does read low, you will still have to determine whether its the fuel pump not making enough pressure or if its the regulator opening and bypassing fuel at too low of pressure.
#17
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From: WI
I'll have to rig a GoPro to it somehow, all of my mounts are screwed into the hull, I don't want to do that to the inside of the engine room
The unit is brand new but I wouldn't be surprised if the regulator is faulty. I still suspect the fuel pump is cavitating or simply too weak / too much restriction. Thanks for the suggestions. Once the cold is over I'll hook up everything and see what the gauge reads!
The unit is brand new but I wouldn't be surprised if the regulator is faulty. I still suspect the fuel pump is cavitating or simply too weak / too much restriction. Thanks for the suggestions. Once the cold is over I'll hook up everything and see what the gauge reads!
#18
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From: Kelowna
id check your key on pressure just to see if its even close, if its a bran new unit you need a external regulator as per the instructions.
hows your A/F sensor mounted. is its reading properly? when mine when bad it did a bunch of weird shat.
not to hard to check fuel pressure well under way, most pressure gauges give you a foot or two of line so you can route it outside the hatch and have someone watch it well you get on it
hows your A/F sensor mounted. is its reading properly? when mine when bad it did a bunch of weird shat.
not to hard to check fuel pressure well under way, most pressure gauges give you a foot or two of line so you can route it outside the hatch and have someone watch it well you get on it
#19
The fuel pressure tester I got from Harbor Freight similar to this one had about a 4' long hose Basic Fuel Injection Service Kit (harborfreight.com)
#20
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From: WI

The fuel pressure tester I got from Harbor Freight similar to this one had about a 4' long hose Basic Fuel Injection Service Kit (harborfreight.com)




