Melted relay block help

[jonheld]

One of the things I like to do is paste sections of schematics together from the EWD to get a better picture of the entire system.
Attached you'll find the entire 94 ECU with all related components in 1 hi-res PDF.
This makes it far easier to see what's what, and who's connected to who.

There's also the power source flowchart where you can see where things are supposed to go.

 

[NeverFinis]

One of the things I like to do is paste sections of schematics together from the EWD to get a better picture of the entire system.
Attached you'll find the entire 94 ECU with all related components in 1 hi-res PDF.
This makes it far easier to see what's what, and who's connected to who.

There's also the power source flowchart where you can see where things are supposed to go.

Great idea! I need to do this ASAP, print it out, and laminate it.

I had electrical gremlins on the way to Cruise Moab and is it hard to read a schematic on a phone on the road.....waited to get home to fix the issue: EA2 connector was not fully connected.

 

[alia176]

Great idea! I need to do this ASAP, print it out, and laminate it.

I had electrical gremlins on the way to Cruise Moab and is it hard to read a schematic on a phone on the road.....waited to get home to fix the issue: EA2 connector was not fully connected.

I just carry the EWD in the 80 when I go on trips, LOL!!! Even though I downloaded the EWD into the tablet, I prefer hard copies as well.

 

[jonheld]

Great idea! I need to do this ASAP, print it out, and laminate it.

I had electrical gremlins on the way to Cruise Moab and is it hard to read a schematic on a phone on the road.....waited to get home to fix the issue: EA2 connector was not fully connected.

I have done this with almost all multi-page schematics from the 91 and 96 EWDs along with the LX450 and some from the 94. All with Photoshop.
Takes a bit of time to get it just right, but makes it much easier to troubleshoot systems.

 

[atm0706]

One of the things I like to do is paste sections of schematics together from the EWD to get a better picture of the entire system.
Attached you'll find the entire 94 ECU with all related components in 1 hi-res PDF.
This makes it far easier to see what's what, and who's connected to who.

There's also the power source flowchart where you can see where things are supposed to go.

Wow thank you very much! Thats a great idea. This experience has been the first time I’ve ever looked at a vehicles wiring diagram and it’s a bit overwhelming

 

[Brindleboxer]

I would say that you may still "want" to pull the intake and check those wires. While the intake is off I would also look at the main harness that runs near the EGR and ensure that it also is not needing attention. There is a clip that tends to break and allow the harness to come either in contact or extremely close to the EGR and it will melt causing various electrical issues. Given the state of you wiring I would take the hit and spend the couple dollars for the gaskets and give yourself room to inspect and work.

Also, look over the wiring diagram and get a fusible link and figure out how to get the system back to stock. Once you think you have fixed all the issues ensure you check out the electrical with a multimeter before trying to actually start the vehicle.

 

[atm0706]

The engineers who designed how a lot of this stuff is routed and oriented should be shot… I ended up removing the intake manifold to gain access to the wires I need to repair, only to find out that the harness is captive between the runners of the lower half of the manifold, preventing you from removing it.

I ended up just cutting the bracing between the two runners to remove it. Decided to do an EGR delete while I’m in here because screw that thing. It was SO in the way. Same with the pesky heater hose pipe, I just cut the bracket because accessing the bolt securing it to the manifold was impossible to get any tools on. Also cut the rear most nut and stud off the lower intake manifold for the same reason. It’s like they only ever intended to have anything on this side of the engine serviced with the engine out of the truck…

Currently waiting on some wire and some other parts to get delivered so I can finish it up.

 

[alia176]

The engineers who designed how a lot of this stuff is routed and oriented should be shot… I ended up removing the intake manifold to gain access to the wires I need to repair, only to find out that the harness is captive between the runners of the lower half of the manifold, preventing you from removing it.

I ended up just cutting the bracing between the two runners to remove it. Decided to do an EGR delete while I’m in here because screw that thing. It was SO in the way. Same with the pesky heater hose pipe, I just cut the bracket because accessing the bolt securing it to the manifold was impossible to get any tools on. Also cut the rear most nut and stud off the lower intake manifold for the same reason. It’s like they only ever intended to have anything on this side of the engine serviced with the engine out of the truck…

Currently waiting on some wire and some other parts to get delivered so I can finish it up.

you GO dude, lol! I've thought the same things in the past. Couple of those VSVs under the intake oughta be outside for ease of service, and to swap out the vac hoses.

 

[Old Nick]

The engineers who designed how a lot of this stuff is routed and oriented should be shot… I ended up removing the intake manifold to gain access to the wires I need to repair, only to find out that the harness is captive between the runners of the lower half of the manifold, preventing you from removing it.

I ended up just cutting the bracing between the two runners to remove it. Decided to do an EGR delete while I’m in here because screw that thing. It was SO in the way. Same with the pesky heater hose pipe, I just cut the bracket because accessing the bolt securing it to the manifold was impossible to get any tools on. Also cut the rear most nut and stud off the lower intake manifold for the same reason. It’s like they only ever intended to have anything on this side of the engine serviced with the engine out of the truck…

Currently waiting on some wire and some other parts to get delivered so I can finish it up.

When you delete your egr I’d recommend this… 1993-1994 FJ80 EGR Temp Sensor Test Plug Kit - https://huddexpo.com/1993-1994-fj80-egr-temp-sensor-test-plug-kit/

Since you’re going all the way, delete the egr pipe completely and throw a block off plate on the pipe’s opening.

I just used the pipe’s mating surface as a template and made my own block off… some high temp gasket maker, bolt the plate in and forget about forever.

The HUD Expo resistor takes care of the rest.

 

[atm0706]

When you delete your egr I’d recommend this… 1993-1994 FJ80 EGR Temp Sensor Test Plug Kit - https://huddexpo.com/1993-1994-fj80-egr-temp-sensor-test-plug-kit/

Since you’re going all the way, delete the egr pipe completely and throw a block off plate on the pipe’s opening.

I just used the pipe’s mating surface as a template and made my own block off… some high temp gasket maker, bolt the plate in and forget about forever.

The HUD Expo resistor takes care of the rest.

Thanks for that! I’d read that a paper clip as a jumper between the pins on the 93/94 works, so I just cut off the sensor and crimped the two wires to each other and plugged it back in. Hope it works or I’ll just order this plug. But I also did make my own block of plates for the egr on the head and intake manifold. Way cheaper than ordering them.

I’m going to probably delete the pair valve as well since it’s mostly pointless now. I don’t have emissions testing where I live, and the cats are already gone thanks to a previous owner. Then I’ll move the o2 sensors to the flanges the air pipes used to be once I finish rewiring them

 

[atm0706]

you GO dude, lol! I've thought the same things in the past. Couple of those VSVs under the intake oughta be outside for ease of service, and to swap out the vac hoses.

Yeah it’s definitely not easily serviceable lol. I think I can get rid of a couple of the VSVs now that the egr is gone, and the pair valve soon to follow. I haven’t checked to see which yet though

 

[Old Nick]

Thanks for that! I’d read that a paper clip as a jumper between the pins on the 93/94 works, so I just cut off the sensor and crimped the two wires to each other and plugged it back in. Hope it works or I’ll just order this plug. But I also did make my own block of plates for the egr on the head and intake manifold. Way cheaper than ordering them.

I’m going to probably delete the pair valve as well since it’s mostly pointless now. I don’t have emissions testing where I live, and the cats are already gone thanks to a previous owner. Then I’ll move the o2 sensors to the flanges the air pipes used to be once I finish rewiring them

You’re rolling through this in a hurry and you’re already doing/done everything that I was going to suggest. Get that crap out of there. It’s great to live in a no smog testing area.

 

[atm0706]

You’re rolling through this in a hurry and you’re already doing/done everything that I was going to suggest. Get that crap out of there. It’s great to live in a no smog testing area.

Still waiting for my wires and gaskets to arrive so I can finish this all up. Did you happen to also remove all the vsvs on the bottom of the intake manifold on your truck too? I’m contemplating doing this while I’m in here just to simplify everything. I found a thread of people talking about it and some people said they had issues with hot starts, and others did not after deleting the fpr vsv and running a line direct to the fpr from the manifold.

 

[Old Nick]

Still waiting for my wires and gaskets to arrive so I can finish this all up. Did you happen to also remove all the vsvs on the bottom of the intake manifold on your truck too? I’m contemplating doing this while I’m in here just to simplify everything. I found a thread of people talking about it and some people said they had issues with hot starts, and others did not after deleting the fpr vsv and running a line direct to the fpr from the manifold.

I didn’t delete it but added new hoses for everything under the plenum. I had starting issues (my truck was all fawked up too). Mine were redone to a failed (new) fuel pressure regulator. It kept killing fuel pumps. Lots of ups and downs, strikes and gutters, but the rig runs like a top now.

I’m sorry that you’re stuck cleaning up po budge jobs. But, once you do, you love your truck.

One last thing. If the port installed alarm is still in your truck… pull it. The “brain” is under your driver’s seat.

 

[atm0706]

I didn’t delete it but added new hoses for everything under the plenum. I had starting issues (my truck was all fawked up too). Mine were redone to a failed (new) fuel pressure regulator. It kept killing fuel pumps. Lots of ups and downs, strikes and gutters, but the rig runs like a top now.

I’m sorry that you’re stuck cleaning up po budge jobs. But, once you do, you love your truck.

One last thing. If the port installed alarm is still in your truck… pull it. The “brain” is under your driver’s seat.

I really hope that it fires up and runs after all this is over and there’s not more to chase down. That’s good to know though, I was super excited to get an 80 series but this whole experience has me considering letting it go after I get it running and waiting for a cleaner one. It’s also been repainted and the paint is trash. I was willing to overlook that since it was supposed to be a strong runner. Now I have an ugly truck that also doesn’t run lmao, and I feel I overpaid for this. It was 12k... We’ll see though. Once I get it running I plan to drive it for a bit at least.

Mine does indeed have that alarm computer under the seat. Do most just unplug it? Or trace back and remove all the wiring as well? I’m sure it’s been messed with too. The security light/thing on the dash is installed upside down

 

[Old Nick]

I really hope that it fires up and runs after all this is over and there’s not more to chase down. That’s good to know though, I was super excited to get an 80 series but this whole experience has me considering letting it go after I get it running and waiting for a cleaner one. It’s also been repainted and the paint is trash. I was willing to overlook that since it was supposed to be a strong runner. Now I have an ugly truck that also doesn’t run lmao, and I feel I overpaid for this. It was 12k... We’ll see though. Once I get it running I plan to drive it for a bit at least.

Mine does indeed have that alarm computer under the seat. Do most just unplug it? Or trace back and remove all the wiring as well? I’m sure it’s been messed with too. The security light/thing on the dash is installed upside down

Yeah, the alarm needs to be systematically unplugged. Then you’ll need to plug the DS harness connectors back together. The connections are obvious. Get rid of that thing.

As for fixing and then selling the truck, I get it. But after you do all of the work to get the rig running well, you still might reconsider.

If you do sell it, look for 80s being sold here in the Mud classifieds.

 

[mudgudgeon]

I was super excited to get an 80 series but this whole experience has me considering letting it go after I get it running and waiting for a cleaner one.

Get it running and drive it for a while. You might see things differently.

Lots of 80s owners have similar experience, buying trucks that need work that makes you question your life choices, but then after fixing them, and driving them, it all still makes no sense at all, but we keep them anyway

 

[atm0706]

Small update.

Been waiting for the shielded wire I needed to fix the o2 sensor wires. It finally came, and I rewired it from the H7 o2 sensor connector back to where it meets back up with the main harness under the intake manifold. I wanted to be sure this fixed it, so I tried to use my multimeter to test it afterward. I unplugged the ECU and tried to measure continuity and resistance from the ecu plug to the o2 sensor plug and I got nothing… I tested the OX1 pin and the HT1 pin and got nothing on either one. I’m not sure if I’m doing this correctly though. But it seems there’s a break in the wiring somewhere else that I haven’t found yet. I ordered a circuit tracer tool so maybe that will help?

If anyone else has any ideas, let me know. I’m a little hesitant to reinstall the intake manifold and try to start it until I know the wiring is good so I don’t have to tear it apart again.

While waiting for everything I cleaned all the oily carbon buildup from the intake manifold and the ports on the head, painted the manifold with Seymour cast blast, cleaned my injectors inside and out, and deleted the pair/egr and all the vsvs under the manifold. Just want this thing to be simple when it works

 

[petegangies]

I’d say with a 80 series it’s best to have money and skills if you don’t want to get ruined financially, boy there’s nothing like getting a 80 series that has had next to no upkeep or years of questionable work done to it. I get 20% off of OE parts through my shop and I still spent well over 800-1000 in parts getting the cooling system dialed and vacuum / PCV refreshed and I did all the work myself which took about 12 hours to do although some time was just spent cleaning parts up.

that's cheap, I'm up to $12k so far haha.

 

[MissahPapaJ]

that's cheap, I'm up to $12k so far haha.

Oh buddy I’m just getting started, some people think paying 10-20k on a 80 series is preposterous but if it’s in good condition it’ll save you in the long run. I bought mine for 1000$ I’d have to do the math but I’m closing in on 5k excluding the 1000$ entree fee. If you count the 30-40 hours of my skilled labor too I’d say I’m probably in your same boat. If I had to pay 150$ a hour to get someone to work on my rig I’d be living in it. I may be wrong about the 30-40 hours it may be more I’ve lost track. I also probably have 1k in parts not installed and have no lift or armor… not a pissing contest just how it’s shaking out.