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85 4Runner Fuel Issue....

Heres the deal Bob Roggy at Roggy Ent. has finished my coil conversion in the rear of the 4Runner the installation is tits to say the least. As a result I have had to install a remote 22 Gal. fuel cell from Summit and a fuel pump on the frame rail. Orginally I hooked up the wires from the new feul pump to the existing factory wires which travel through the factory harness (Excluding the sender wires for the fuel level in dash gauge). On first attempt to start the truck it ran for apprx. 2 sec.......then all it would do is key start and keep turning over.

I checked fuses and came to find I had popped a 10a under the dash I raplaced that fuse and tried again.....same results except I didnt blow the fuse. Since this first incident there is no power to the factory wires????

To date I have installed a remote wire for the fuel pump, along with a 15a fuse to a dash mounted toggle. Hoping this would solve the problem I attepted another start of the motor. Currently it starts and runs for about 1 sec. and then dies???? I am at lose as to why this is happening. Another note is that the fuel pump keeps on running with fuel pressure at the EFI on the engine....I checked the check valve on the EFI unit on the motor to make sure its delivering fuel....it is .

Everything is grounded, the factory charcoal canister line is open from the engine compartment (which shouldnt matter?) The new pump is running at 97 PSI (I was told a factory Toyota fuel pump for EFI motors run at 90PSI.

My next thoughts for tonights troubleshooting are to look at the factory wiring and trace it ...................is there another fuel pump relay I could have blow in line?? If this wiring is good hook it back up to the stock wiring and see what happens.

Questions:

Do I have the right PSI Pump?

Does the factory Toy Fuel pump have an internal on and off switch for pressure?

Do I have to regulate this pressure?

Does the tank have to be grounded?


Any information would be helpful.....UGET IT


This is UGET IT over at Lance house drinking Cabo Wabo Tequlia....LOL
 

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Lance---you should see it regulating at just under 40 psi......there is a regulator somewheres near the top passenger side of the engine.
 

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This is UGET IT.... The only thing I can find in the engine compartment is the fuel filter attached to the motor. Jesus 47psi is what someone is saying on the General section........if thyats the case I have the wrong fuel pump. Does anyone have a part number for the correct aftermarket fuel pump?
 

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Is this a 22RE?

If so the regulator is vacuum/mechanical and located at the rear end of the fuel rail. A rubber fuel line attaches to it and of course goes to the tank. If this is not hooked up my only guess is that there is too much pressure in the fuel rail.

Now the ?? for the experts: Will too much pressure in the fuel rail stop the injectors from firing??

UGET IT: I don't think it's necessarily a problem that the pump is making 90psi. The regulator should keep the rail pressure at the right level.
 

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My problem when running Summit fuel cell to factory wiring turned out to be ground up front. Pretty sure it was the engine ground, but whatever, everything else worked but the fuel pump. Make sure your factory grounds are all in place.
I looked quite a bit at external pumps and they all told me factory for an 87 pickup was 67 pounds. I'm running a 60 pound now and it works fine, all except the noise issue. It's so loud I'm going to pull it.
By the way, you can use the factory fuel gauge lines and tie them into the Summit cell. It will just read upside down, Empty is Full and vice versa.
 

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I run a summit aluminum fuel cell with a factory 85 toyota (in-tank) fuel pump. I just bolted it in and it worked fine. From the factory it is wired through a relay that doesn't let it run with just the key on but I have wired it straight to the battery and it worked fine also. I had one that would start up and then sieze up and blow the fuse before so make sure the fuel pump keeps runing. Also, a 22re is equiped with a "cold start injector" that injects fuel in the intake when you crank it over cold so it will start. If this fails it will start and then immediatly die 5 or 6 times before it will finally start and keep runing. Make sure this is not your problem either.
 

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Even with the pump dead headed at 97 psi, it shouldn't blow the fuse. a frame rail pump doesn't need to have a grounded fuel tank. The factory pump uses the efi relay to fire the pump. The aftermarket pump may need its own relay if it draws a higher amperage. Did the new pump come with a fuse size recomendation? It sounds like you may have got a bum pump to me.
I would unhook the pump and pull the fuse and efi relay. Then take an ohm meter and check the resistance to chassis ground at the fuse. It should be open (>10k ohms). If not ,you have a wiring short between the fuse and the relay. Then check the wire at the fuel pump end for continuity to ground. It should still show open. If not you have a short between the efi relay and the pump. If these check out good, the pump is bad.

I would wire an aftermarket hi- perf. pump with it's own relay wired to be triggered by the ignition switch. I then would run it's own ground directly to the frame from the negative post of the pump.

Oh, and 85TrailToy, too much fuel pressure won't stop an injector from firing. They use an electo-magnet to pull open a pintle valve and there is no surface that the fuel pressure could press to keep the injector closed.

The fuel pressure is regulated at the engine, with the excess returned to the tank via the return line. If the return is plugged., or the regulator on the engine stuck, you will have way too much fuel pressure.
 

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Lance said:
OK so whare is the stock 85 EFI Relay for the fuel pump? Desret Toy dont you run an EFI with an aftermarket pump?

This is UGET IT
I believe passenger side kick panel. I hear mine click.
 

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zags said:
I would wire an aftermarket hi- perf. pump with it's own relay wired to be triggered by the ignition switch. I then would run it's own ground directly to the frame from the negative post of the pump.
Larry.....wouldn't it be better to trigger the new relay
with the stock fuel pump wire to retain the stall
protection feature? That way if the fuel line breaks
or splits causing the engine to die, the pump doesn't
keep spewing out fuel.

Jay
 

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ROKTOY, you have a good point, and in a catastrophic accident it could provide some additional margin of safety. But in a trailered trail rig, the odds of completely severing a fuel line seem mighty slim. Even with a rubbed through fuel line leaking, the pump is capable of much more volume than the motor uses. An EFI engine will still run with as little as 10 PSI. of fuel pressure(albeit not very well), and continue to run for a surprising amount of time just gravity feeding from the injector rail. I guess my way of thinking is along the lines of having a simple, dependable, heavy duty circuit solely dedicated to the fuel pump, especially if it is a high performance pump with a higher amperage draw than a stock one. Remember, this circuit may have to be diagnosed trailside some day, so my opinion is “the simpler the better.”
I’d have to look at a wiring diagram again to see if one could wire the new fuel pump relay to be triggered by the stall protection circuit directly, thus eliminating the stall relay.
 
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