1991 Land Cruiser 175,000 miles. Intermittent problems with maybe the fuel pump or relay. Doesn't start every time but turns over strong. Has anyone ran into this issue before?
Fuel pump
- Thread starter LandCruiser91
- Start date
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If you suspect a fuel delivery issue, first thing I'd do is to check the fuel pressure using a gauge. You can rent them for free at a typical auto parts store. Otherwise, you're just guessing and throwing parts at the problem.
Good luck amigo.
- Thread starter
- #4
Haven't had a chance to work on it much. Starts with a shot of ether in a vacuum line. Starter was not much of an issue. Starter wire wasn't making good contact. Fixed that in a jiffy. I'll have some time this week to look her over and get the fuel pressure gauge.
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- #5
After checking everything, but not finding a banjo fitting to do a pressure check, I replaced the fuel pump, and she fires right up. One small problem solved, a few more small things to go. Thanks for all info. I'm sure I'll be back for more
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- #6
Grrrrr.. worked great for a few times. Doing the same thing again. Power comes from the battery, to the efi relay, to the circuit opening relay, to the fuel pump relay and on to the fuel pump. I can't find any relays other than the efi main. Any info helps.. geez!
I'm not sure where you're getting your information from.Grrrrr.. worked great for a few times. Doing the same thing again. Power comes from the battery, to the efi relay, to the circuit opening relay, to the fuel pump relay and on to the fuel pump. I can't find any relays other than the efi main. Any info helps.. geez!
The fuel pump is fed from the circuit opening relay.
The COR has 2 coils (logic). The primary is fired when cranking the starter, and the secondary is fired when the flap in the AFM opens as the motor begins to draw air into the intake.
+12 for the COR load side is fed from the EFI relay/fuse. There is no "fuel pump relay" on a US spec 3FE equipped 80 Series.
You can bypass all FP logic by shorting pins 1 (FP) and 8 (B+) in the diagnostic connector on the firewall. This will fire the FP when the key is in the ON/RUN position and should only be used as a diagnostic.
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- #8
Thanks a ton. I'll try it.
Haynes Land Cruiser manual page 4B-8. Page 12-42 shows the 3 relays and the fuel pump resistor. That's the electrical circuit, I can't find em anyways, so I'll do what you suggested and hopefully have this beast fixed soon.
Haynes Land Cruiser manual page 4B-8. Page 12-42 shows the 3 relays and the fuel pump resistor. That's the electrical circuit, I can't find em anyways, so I'll do what you suggested and hopefully have this beast fixed soon.
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- #9
And is the COR the same as the EFI relay? That's what's got me cornfuzzled.
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- #10
One more thing... It runs fine after you fire it up using a shot of ether for the startup.
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- #11
No.. damn, just saw that.. sorry
Haynes manual is wrong and should be thrown in the trash. There is no substitute for the Toyota Factory Service Manual (FSM) and the Toyota Electronic Wiring Diagram (EWD). Anything else is going to lead you astray.
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- #13
Yeah.. sounds like crap, no doubt.
I googled and found the COR. Drivers side kick panel. I took it out and the "good" is 50-120 ohms. Mine is reading 26-27. I think I may have found the problem.
I googled and found the COR. Drivers side kick panel. I took it out and the "good" is 50-120 ohms. Mine is reading 26-27. I think I may have found the problem.
The 91s are know for bad EFI relays. If you haven’t swap it out.
@LandCruiser91 Please keep us posted when you pinpoint it what it is.
I also have a 91 and still trying to track down the source of my intermittent no start issue. And for the record, I replaced my fuel pressure regulator already and still have the issue.
I also have a 91 and still trying to track down the source of my intermittent no start issue. And for the record, I replaced my fuel pressure regulator already and still have the issue.
@LandCruiser91 Please keep us posted when you pinpoint it what it is.
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- #17
I'll let you know tomorrow when the part comes in. Hopefuyrhis will help us both@LandCruiser91 Please keep us posted when you pinpoint it what it is.
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- #18
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- #19
You replaced the regulator, I replaced the pump. We're gonna have a new vehicle before long.@LandCruiser91 Please keep us posted when you pinpoint it what it is.
I'm sure hoping this solves both our problems.
A faulty FPR typically manifests itself as hard starting when hot.
It will overpressurize the fuel rail and the check valve in the fuel pump will stick closed.
It will overpressurize the fuel rail and the check valve in the fuel pump will stick closed.