Builds My "ran when parked" Land Cruiser from Craigslist (5 Viewers)

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I plan on cleaning the injectors, so that's probably no a bad idea.
While it's very unlikely that a shorted injector wire would take out the EFI fuse as the injectors are not fed from that fuse, those connectors are 32 years old and likely very brittle. Be sure to have some new connectors on hand as well as some pins before you start.
Connector 90980−10720. Pins w/pigtail 82998-12270.

In the Engine Control section of the EWD, you'll see that the EFI fuse feeds constant +12 to the ECU.
It also feeds the EFI MAIN relay which powers the entirety of the EFI system.
Follow the Y-R wire that goes through connector EB1, and you'll find all your suspects right through the circuit opening relay (COR) that controls the fuel pump.
If you simply unplug the COR you have eliminated a strong possibility.
Divide and conquer with a meter and the EWD.
 
Yeah, that BO1 connector is definitely low-hanging fruit and worth confirming whether it's an issue or not due to its exposure to the elements.

But there is something going on with that tank hatch assembly. The OP notes a relatively clean truck, but doesn't note how many miles are on it. My LX 450 had around 325000 when I acquired it, with a relatively clean body from spending most if its time in the dry Southwest. I got it in Michigan, where it resided the last 2 or 3 years, but the owner said she parked in for the winter inside. The top of the tank really gets very little exposure to splash. I suspect there's some sort of condensation process going on possibly from the tank line drawing cold fuel that causes moisture to bead up around the fittings on the tank hatch thus initiating the process that causes corrosion underneath the plastic button covers.
It's got 194,000 miles on it. Don't know why I left that out.
 
Small update:
I needed to move my Land Cruiser, so I hooked up a 12v UPS battery directly to the fuel pump. It started right up. It rained all weekend, so I didn't get a chance to look at the wiring. Now that I can move it, I can get it into the garage if I need to. Still seeing more lizard poop, so I'm going to wash the interior with some Dr. Bronner's peppermint soap. Peppermint is used in commercial lizard repellant, so we'll see how that works. I've been studying the wiring diagram and I have a better idea where to look. I appreciate all the help and recommendations I've gotten so far. It runs pretty good despite the secondary air pump being disconnected. I ordered the air injection valve from cruiserparts.net, so hopefully I can get that hooked back up soon. I might take the old valve to work and see if someone can weld a new outlet to it so I can have a spare.
 
Small update:
I needed to move my Land Cruiser, so I hooked up a 12v UPS battery directly to the fuel pump. It started right up. It rained all weekend, so I didn't get a chance to look at the wiring. Now that I can move it, I can get it into the garage if I need to. Still seeing more lizard poop, so I'm going to wash the interior with some Dr. Bronner's peppermint soap. Peppermint is used in commercial lizard repellant, so we'll see how that works. I've been studying the wiring diagram and I have a better idea where to look. I appreciate all the help and recommendations I've gotten so far. It runs pretty good despite the secondary air pump being disconnected. I ordered the air injection valve from cruiserparts.net, so hopefully I can get that hooked back up soon. I might take the old valve to work and see if someone can weld a new outlet to it so I can have a spare.
By "secondary air pump" are you referring to the belt driven smog pump on the left side of the motor?
If so, leaving it disconnected will not affect anything. The smog pump is only active under very specific conditions.
 
By "secondary air pump" are you referring to the belt driven smog pump on the left side of the motor?
If so, leaving it disconnected will not affect anything. The smog pump is only active under very specific conditions.
The smog pump is what I'm talking about. I disconnected one side of the hose and the other side just fell off because 90917-10076 was rusted. The issue that I figured was related to that or the EGR was that the exhaust smelled really rich and I had to push the gas pedal down quite a bit to even get the truck to move. Maybe it just needs a tune-up, or I'm just accustomed to the throttle response in my FR-S and it's just something to get used to. I'm also wondering if the emergency brake is dragging a little because the brake light didn't turn off when the lever was disengaged.
 
The smog pump is what I'm talking about. I disconnected one side of the hose and the other side just fell off because 90917-10076 was rusted. The issue that I figured was related to that or the EGR was that the exhaust smelled really rich and I had to push the gas pedal down quite a bit to even get the truck to move. Maybe it just needs a tune-up, or I'm just accustomed to the throttle response in my FR-S and it's just something to get used to. I'm also wondering if the emergency brake is dragging a little because the brake light didn't turn off when the lever was disengaged.
Only 2 items trigger the dash BRAKE lamp.
The switch in the handbrake lever and the float switch in the brake fluid reservoir cap.

As far as engine power, while the 3FE is a bit under powered, it should have no trouble moving the truck right along.
Make sure the transmission fluid is bright red and at the correct level once warmed up.
You're not in 2nd are you?

Putting it on jackstands will tell you if you're brakes are dragging.
 
I'm pretty sure I wasn't in second because it was behaving the same in reverse. Low transmission fluid would definitely make sense. I haven't had it on level ground since I got it because it's too heavy to push into the garage, so I've been working on it in the street and in the driveway. I had to use a hand winch and the hitch on my FR-S to get it in the driveway because the city put an abandoned vehicle sticker on it. I'm planning on changing the oil and checking all of the fluids once I get the wiring issue fixed. The coolant is a nice shade of brown, so that is overdue for a flush. The brake fluid looked okay, so I might need to check the switch.
 
I'm pretty sure I wasn't in second because it was behaving the same in reverse. Low transmission fluid would definitely make sense. I haven't had it on level ground since I got it because it's too heavy to push into the garage, so I've been working on it in the street and in the driveway. I had to use a hand winch and the hitch on my FR-S to get it in the driveway because the city put an abandoned vehicle sticker on it. I'm planning on changing the oil and checking all of the fluids once I get the wiring issue fixed. The coolant is a nice shade of brown, so that is overdue for a flush. The brake fluid looked okay, so I might need to check the switch.
A quick note:
The A440F transmission is somewhat finicky when it comes to fluid level.
What I typically do is run some errands with the truck to get things up to normal operating temp. Then park on a somewhat level surface with the engine running. The fluid level should be just up to the top of the HOT mark on the dipstick and the fluid should be bright candy red.
 
Low transmission fluid will result in car wont stay in gear or unable to engage 1st gear at a stop. check the fluid level per Jons above and shift back and forth into drive and all the gears to get the fluid pressure up.
 
Friday, I inspected the wiring a bit more. Still haven't found anything, but I'm going to keep looking. Saturday was nice outside, so I rolled the windows down and paired my phone to the headunit and listened to music while I cleaned the animal poop out of my truck. I sprayed the interior with a mixture of 1/4 cup of peppermint castile soap to 32oz of water. I got a lot of tar cleaned up because the previous owner is a smoker. I suspected it was a lizard because a bird was too large to not notice in there, but I was wrong. I found a dead sparrow in the back underneath one of the third row seats. Luckily, I found it before it started to decay. I dug a small hole in my backyard next to my garden and had a bird funeral. Hopefully I don't get bird flu.

One less thing to distract me from what I need to work on now. Bonus, I found the nut/washer (90179-10074) that holds the gas tank latch, so now the outer gas cap closes and I can take that off of my parts list that I need to order.
 
If you strip to the shell, a bleach solution can be helpful for animal odors. I restored a porsche that had been infested by rodents this way. The carpet and seats were shot, but I eventually got the smell out of the shell and harnesses.
 
I've been busy the last few weekends and ADHD has been getting the best of me, but I got a little time to work on my truck this weekend. I got an Autel PS100 to get a better idea of the electrical problems. I found another blown fuse for the rear defrost, not sure what is going on there. The hitch wiring looks pretty bad, so I need to undo/redo that. I crawled under it before I bought it to look at the frame and didn't notice how mangled it is where the front bumper mounts to the frame. Luckily nothing that will affect the alignment, but I don't know how I am just now noticing it. My dad is a welder, so I guess we'll have to figure that out at some point. I definitely need to spray it with rust encapsulator for the time being as it's the only part of the frame that's rusty.

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The hood has the vacuum diagram for a 1FZ, so it was replaced after the front end collision that caused the damage above.
I found some more questionable wiring. I'm going to put this in wiring loom and retape it since it's running next to the hot engine.
IMG20250330153535.jpg


I depinned, trimmed, and recrimped a wire that had a crack in the insulation.
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I have a question. Should there be voltage on the fuel sender? The red wiring going to the fuel sending unit had 12v after turning the key. Could the wires for the fuel sending unit and the fuel pump be swapped?

I also tested the EFI and COR relays with the probe and they activate when the probe is energized, so those are both good.

I tested all 4 pins of the relay connector. Pin 1 was ground (0V), Pin 2 was 11.6V, Pin 3 was 0.4V, Pin 4 was 10.6V. Should I expect that voltage drop, or is that something I should look into?
 
I have a question. Should there be voltage on the fuel sender? The red wiring going to the fuel sending unit had 12v after turning the key. Could the wires for the fuel sending unit and the fuel pump be swapped?
If you look in the COMBINATION METER section of the EWD, you'll see that the fuel sender is a resistor to ground. The fuel gauge gets +12 from the GAUGE fuse and the sender varies the voltage to move the needle. So yes, you would see voltage through the gauge to the sender.

You'll also notice that the fuel pump does not run with the key in the ON position. It only runs when the starter is engaged and when the flap in the AFM opens. That's why there's 2 coils that fire the COR.
I also tested the EFI and COR relays with the probe and they activate when the probe is energized, so those are both good.
For reference, that is not a valid test for a relay. Even if you hear a relay activate, the internal contacts on the closure could be pitted and faulty.
I tested all 4 pins of the relay connector. Pin 1 was ground (0V), Pin 2 was 11.6V, Pin 3 was 0.4V, Pin 4 was 10.6V. Should I expect that voltage drop, or is that something I should look into?
Again, you're not looking at the EWD. Pin 3 is the logic signal from the ECU that fires the EFI relay and the other side of the coil is ground. If you test that with the relay in place you'll be getting close to 0VDC because you're reading through the coil to ground. The fact that the relay is activating should tell you that the logic from the ECU is good.
Pin 4 is the load side of the relay feeding the rest of the EFI system/sensors. There's a decent load on that terminal so I would expect a voltage drop.
 
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Thanks for pointing me in the right direction. I only had the Engine Control section printed. Still trying to make sense of everything.
 
I think it's the AFM. It's not ohming out correctly. I think when I tried jumping FP and +B on the check connector, I didn't follow the instructions correctly. When turning the key, then jumping those pins, the fuel pump turns on. I think the version of the repair manual that I downloaded previously was incomplete.
 
I think it's the AFM. It's not ohming out correctly. I think when I tried jumping FP and +B on the check connector, I didn't follow the instructions correctly. When turning the key, then jumping those pins, the fuel pump turns on. I think the version of the repair manual that I downloaded previously was incomplete.
Jumping FP to B+ bypasses all FP logic and feeds +12 directly to the fuel pump when the key is in the ON position.
The fuel pump is supposed to run in that condition.
 
Right. If I understand the FP logic correctly, the AFM being bad will prevent the COR from completing the circuit. Which is why it cranks, but the fuel pump doesn't have power. I haven't ruled out there being a short somewhere, but this would explain the fuel pump not turning on at all.
 
Right. If I understand the FP logic correctly, the AFM being bad will prevent the COR from completing the circuit. Which is why it cranks, but the fuel pump doesn't have power. I haven't ruled out there being a short somewhere, but this would explain the fuel pump not turning on at all.
The fuel pump should fire while cranking the starter. That is the function of the primary coil of the COR. That coil is energized from the starter circuit. The secondary coil is energized when the flap in the AFM opens.

The 2 coils are fired from 2 separate circuits. If neither of those 2 circuits fire the COR, then it could be the issue.

Have you verified the COR and the 2 logic paths?
 

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