80 series fuel pump or fuel pressure regulator issues (1 Viewer)

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The '96 EWD which is available around here shows the relay positions in the left kick panel:

1615162250656.png


In mine the square relay is, indeed, the heater relay, but it is bottom/center.
 
I'm not quite sure what orientation this is supposed to be but...

The heater relay is in the center, towards the door and in the center towards the fire wall is the tail lamp relay. The flasher is separate, up and towards the firewall. I haven't mapped the others, but I tested them all and they all work. There is one relay position near the flasher that is an empty socket.
 
Which pg of the EWD did you cite, and did you pull that ring terminal that feeds the new ‘hot wire’ -from power before you posted the CEL status?

I’m very willing to grab my ‘97 EWD & help, but we need to be talking the exact same English - and that thermal-reset breaker is a ‘wild card’ -when you don’t post the exact status of it when you’re troubleshooting / CEL spectrum of this situation.

—————————

You really need a local shop (only one I hear repeated alot is George’s Hybrids down in Cali, no idea their location) - if you feel this is over your experience or desire to roll up the sleeves & get crazy on.

That or a open call on the local Cali clubhouse for guys who know the late 1FZ EFI - you have a TON of guys down there I’d ask nice & offer beer/pizza, etc -to look at your 80 in person.

Guys I’d do the same if it was my 80 & I wanted it for the long-term. I’m not going to tag them, but you live in ‘80-guy central’ IMO.

You live by a ton of great guys, I’d reach out myself. :meh:
 
Here's another one that's the same as mine from LandCruiserPhil's power window hack thread.

IMG_4236.jpg


So going across L->R and top to bottom, ??, power windows, flasher, heater, tail lights empty, ?? is the bottom one and there's only one on the bottom row.
 
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Which pg of the EWD did you cite, and did you pull that ring terminal that feeds the new ‘hot wire’ -from power before you posted the CEL status?

That is the same as removing one leg of the fusible link, the W-R on page 52 & 54. Removing that, for sure, kills the CEL regardless of the EFI relay/fuse in or out.

I’m very willing to grab my ‘97 EWD & help, but we need to be talking the exact same English - and that thermal-reset breaker is a ‘wild card’ -when you don’t post the exact status of it when you’re troubleshooting / CEL spectrum of this situation.

I don't agree, but I'm happy to jumper the two terminals of it together while I debug if you think that puts us on the same page.

You really need a local shop (only one I hear repeated alot is George’s Hybrids down in Cali, no idea their location) - if you feel this is over your experience or desire to roll up the sleeves & get crazy on.

That or a open call on the local Cali clubhouse for guys who know the late 1FZ EFI - you have a TON of guys down there I’d ask nice & offer beer/pizza, etc -to look at your 80 in person.

Guys I’d do the same if it was my 80 & I wanted it for the long-term. I’m not going to tag them, but you live in ‘80-guy central’ IMO.

You live by a ton of great guys, I’d reach out myself. :meh:

I don't know anyone around here with an 80. In Sac and Stockton, for sure, but I'm 2 hours from there. If I can't figure it out, I'll have it towed over to Georg, but throwing more $$ at it is not my favorite thought unless I could get a definitive diagnosis and estimate. I think that would be tough for any mechanic at this point.

Cruiser mechanics are busy. I understand that.
 
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I see now that this diagram matches those pictures with the orientation flipped.

1615168241372.png


So perhaps the one on the bottom row, under this whole circuit board, is the circuit opening relay.
 
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Today I wanted to check the wiring on the bottom of the fuse/relay box under the hood, so I removed the battery, battery box, and the charcoal canister, so I could get under there.

The wiring under there is pristine.

Nothing I tried would get it to start, swapping and checking the relays. I have one extra now so I tried all permutations of the EFI, what I presume to be the circuit opening relay and the new Toyota relay I got. The CEL was on with the EFI relay and/or fuse out. I also tried going back to the old Fuel Pump relay without any difference there.

To get on the same page as Linus, I bypassed the breaker on the IGN leg of the fusible link. CEL out with it disconnected, CEL back on with it bypassed, still did not start.

I gave up for the night and put it all back together, charcoal can, fuse box, battery box, battery. Now it starts (twice). Now the CEL goes out when I pull the EFI fuse. :bang:

I'm sure it will work perfectly for any mechanic demo now, and then it will take a crap next time I go get take-out food.
 
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It sounds like you have an intermittent short / poor amps getting through if it now works like a charm whit a ‘bump/jostle’ of the relay blocks, hopefully with that jumper you have disconnected.

The only reason I harp on it (jumper line) -is I’m not right along side you with a Fluke, measuring all the values of amps being delivered.

The upside is that now that you checked the fuel sock, had it run with the fuel pump you have, and replaced the FR fuel filter under the intake - now it’s down to volumetric flow or fuel injector clogs. **If** it’s mechanical.

But the situation sounds like it’s in the wires, so now you need to get out the multimeter & also look everywhere for aftermarket wires, esp aftermarket alarms or a kill switch.

I’ve only ever removed it once on my old LX450 - but do you have the port-installed alarm that the ECU of it lives under the driver seat?

If so, that as a unit needs to be scrutinized - I’m not sure if it kills the motor via starter kill as I suspect (most common) - or if it kills fuel delivery (less common but how MB & from memory Kia do it).

Or if anybody here can confirm it’s a starter isolator alarm, even if you have it we can rule it out.
I just pulled & pitched mine, they are too old to be reliable any longer.
 
It doesn't have the alarm. I looked for it when I bought this thinking I might be able to get keyless entry working.

Recently this problem has only affected starting. It runs fine, which makes me think the injectors are at least fairly good. It was when driving offroad and up steep hills that it originally stalled out. That seems like wires jostling-then-shorting to me.

In this thread there is a comment, "I am aware of the area below the ECU (behind the PS knee area speaker panel) where some owners have reported the wiring harness can rub against a metal tab and wear through the insulation, causing shorts. " I hadn't read this anywhere before and I haven't checked this (yet).

I also haven't looked at the harness near the EGR tube that has caused some problems in the past.
 
What I don't get is why anyone thinks all the power for the ECM comes from the EFI fuse? In the EWD it clearly shows there is power from the IGN to the ECM, and the signal that closes the EFI relay comes from the ECM. The IGN powers up the ECM and the ECM, in turn, closes the EFI fuse. Why would the CEL not come on regardless of the EFI fuse/relay?
From the 15 amp EFI fuse, the red/yellow wire runs to pin 2 of connector E7, called BATT. That is the constant battery power to the ECU.
Solid yellow pin 12 of E7 tells the ECU that the EFI relay is closed. (B+)
The black/light blue wire from the ignition switch that hits pin 1 of E7 tells the ECU that the ignition switch is ON and is a logic signal. (IGSW) It also provides logic +12 to the COR.
Solid red from pin 3 of E7 is the EFI relay logic. (MRLY)

Without the 15 amp EFI fuse or the EFI main relay, you have a 6000 pound paperweight.
 
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I see now that this diagram matches those pictures with the orientation flipped.

View attachment 2606617

So perhaps the one on the bottom row, under this whole circuit board, is the circuit opening relay.
The orientation is correct in your picture and is exactly what's in the kick panel of every 80 Series From 1991-1997. For some reason, the COR was not shown in later versions of the EWD on this specific drawing.
Below is from the 1991 EWD and it has more detail. The COR was different between the years, but it lives in the same location as all the others. The cooling fan relay was specific to 3FE equipped 80s.

Relay block Left Kick.jpg


Here is the same drawing from the 1994 EWD.

Left Kick.JPG
 
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Got it. My COR is round and I tested it.

Any recommendation where I might have the most success looking for something shorting to that E7/BATT? It really looks like that may be the problem as I, for sure, had CEL with both the relay and fuse removed, and I measured some voltage, around 2.5v at the output (pin 4) of the EFI relay socket with the IGN turned on when it was happening.

Have you heard about the harness in the right kick panel rubbing and shorting before? I thought that sounded promising, but I only read it in that one thread I linked above.

OTOH, I did not disturb the harness in the right kick panel since I didn't drive it or open up the panel.

I did unbolt the relay box on the fender and "disturb" the harness at that location. Every wire I looked at there looked to be in perfect condition, not even dirty. The under-hood condition of this truck is very nice. Of course I realize it's old no matter how it looks. I also plugged and unplugged the fuel pump relay numerous times. I don't see how that matters at this point, since my issue seems to be with the ECU power.
 
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Have you heard about the harness in the right kick panel rubbing and shorting before? I thought that sounded promising, but I only read it in that one thread I linked above.
It has been discussed multiple times and is a potential trouble spot on later model FZJ80s. On my LX450, the lower support for the glovebox was starting to wear through the insulation of the ECU harness that makes a sharp bend in that location. It's pretty easy to prevent further damage once you see what's happening. It was one of the first things I addressed along with the main engine harness by the EGR pipe.
 
I don't know anyone around here with an 80.
You still in the South Bay?

Pretty sure I'm free this weekend if you think you'd like to have another set of eyes on it, and another 80 to compare with.

I wouldn't call myself a Cruiser mechanic, but I have made a living trouble-shooting electrical issues. And besides, I owe you a solid for all your help spotting us on the Snake Lake trail that day!
 
You still in the South Bay?

Pretty sure I'm free this weekend if you think you'd like to have another set of eyes on it, and another 80 to compare with.

I wouldn't call myself a Cruiser mechanic, but I have made a living trouble-shooting electrical issues. And besides, I owe you a solid for all your help spotting us on the Snake Lake trail that day!

Yea, Willow Glen. I have another car project I have to prioritize, but I'll probably be working on it some by Sunday. Thanks!
 
Hey @landcrshr, sorry I never got back to you. The weekend was not on a schedule, so I didn't know when I'd have a chance to work on my 80.

I pulled the glovebox, added a plastic loom wrap and a bit of duct tape there. There was a mark, but it doesn't look to me like there could have been a wire problem.

I inspected the heat wrap near the EGR tube. It looked like it was 24 years old, but it was intact. I wrapped it with a couple wraps of exhaust tape and also wrapped a couple wraps around the EGR tube. I'll need a metal zip tie for that. I didn't think the plastic ones would last to the next food stop in that hot location. I also pulled the harness as far away as it would go and added a zip tie to the OEM hold down near the valve cover. There was ~5mm space before and >20 mm after.

It has started the last 10x I tried, throughout all this work, but I haven't moved it. We'll start driving it around the 'hood now and see how it goes.

beforeGloveBox.jpg



afterGloveBox.jpg


afterEGR.jpg



beforeEGR.jpg
 
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Hey @landcrshr, sorry I never got back to you.
That's cool, I was on call last weekend anyway. You know, just in case the crew at work ran into any electrical issues, lol.

Do you still have the circuit breaker in place, or did you swap in the new fusible links? Honestly, I'd continue to run the breaker until you know the issue has been sorted out. Maybe try doing a few torque-stands to simulate the steep uphill climbs.
 
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