FZJ80 Running Woes (3 Viewers)

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Thanks so much for your detailed reply; I have ordered a FSM which should be here in few days so won't need your generous offer to send me a copy of the procedure to measure fuel pressure. I am having an intermittent hot start problem so fuel pressure drop after engine shut off seems a good issue to check. Thanks again. The car has 289k miles and seems to have the original fuel pump. Do you have an opinion as to whether leaking fuel injectors could be an intermittent problem?
Leaking as in from their O-rings? I feel like that would be apparent from smell/watching it do it as it runs. I've sent mine off to an injector shop when my #6 shorted out (EGR burnt my wires). But it's not unheard of to have injectors sticking open or closed.
I'm going to do a cylinder drop test (maybe tonight after studying?)
Essentially it allows you to pinpoint the problem to a specific cylinder, if it is applicable.
You do this by having the engine idling (while it's experiencing it's running issue). One by one you unplug the injector connector. If there's a problem with (for example) the #2 cylinder (whether fuel/spark/valve/whatever), then when the #2 injector is unplugged, you won't see a change in how it's running. However if that cylinder is functioning normally, when you unplug the injector, then it will run worse. You only want to do it with one cylinder at a time (just making sure you don't have like, half the injectors unplugged).
Along with that, if all 6 result in worse running, then you know that the spark plugs/injectors aren't the issue INTERNALLY. However if one is leaking from an O-ring, then that would be external-ish.
I have heard of the FPR having issues once warm, won't hurt to overhaul the fuel system like I did if you haven't recently. My FPR was original to the car, I believe it was bad. However I'm experiencing multiple issues at once so🤷🏻‍♂️
 
Did a cylinder drop test today. When unplugging injectors #1 and #2, there's no change in the poor running. Subjectively good news to me because I now have the problem child isolated to two cylinders. So three things could be going on; either the injectors are sticking, stuck open, or I accidentally swapped the 1 and 2 injector connectors when rebuilding my harness (although I doubt that last one, I kept everything labelled during the process. I'm just not one to throw assumptions). Also want to add I did the hillbilly test, listen to an extension touching each injector. #1 definitely isnt firing, #2 is hard to tell, but it did sound different. I might've been hearing vibration or a different injector firing or something, BUT I have verified that cyl 1 and cyl 2 are getting spark. So it has to be the injectors.
Last time I chased an issue on my Land Cruiser, ironically, was about 3 or 4 years ago, and my #6 injector had failed.
This time around I'll just replace them all. However I'm going to get my (presumably bad) #1 & #2 injectors hooked up to a bench tester to verify they are the problem children I've been searching for, and will report back. I'll also go ahead and test for signal voltage and ground coming from the ECM on those two injectors jusssssst to be sure everything else is copacetic.

I wanna point out that although I tested lots of things during this process, I honestly didn't have a true method to the madness, which I should've. Rebuilding the harness was something I certainly needed to do, and the issues it had I'm sure weren't helping anything, and if those injectors ARE bad, I'd blame brittle/exposed wires in the harness which I have since repaired properly.
I got to a point where I realized that I was just doing the testing version of throwing parts at the car, which is when I commented about restarting at the basic stuff.
In any diag like this you should start with spark and fuel, and work your way up the ladder. If you have good fuel pressure, is every injector doing its job? If you have spark, is your timing set right? And so on.
The cylinder drop test is super nifty, especially for OBD1, since we don't have the luxury of a full on-board diagnosis system. It allows us to immediately isolate the issue to a single cylinder, or to all of them. If it's all of them, you start to look at what they would share (ie. vacuum leak, AFM, ignition coil, etc.--systems that all 6 cylinders need to run).
 
Second injector came in today (I ordered the first preemptively with other parts just in case, but didn't expect to need two)
Kinda dumb but when I ordered the second one I wasn't at home to see the brand of the first, but I was gonna have them flow matched anyways so as long as it's reman I didn't really care.

Anyways, both injectors are wrong. The GB Manufacturing 842-12131 (pink) has a recessed nozzle, and smaller port holes.
And the Ultra-Power FJ375 (brown) is a reman Supra 2JZ injector, which is 312cc whereas the 1FZ is a 450cc

I ordered both through RockAuto where they're listed (and I double checked) for a 93 Land Cruiser...

Their customer service is 100% online, not even with people on the other end. Essentially RockAuto wants me to split the cost of shipping these back to them🙄 which has me ticked off. Unfortunately can't reach anyone to help when I call corporate.
Never ends I guess😂😂

I don't think I'm going to get my replacement injectors through them. I'm just gonna get a refund and order a set of the upgraded 4-port Bosch injectors from CruiserParts. I know I'll get good customer service AND the right parts. Plus upgrades, people! Ammiright

Shaking my head at RockAuto, as this is now making me second guess everything else I've ordered through them, like the fuel pump and regulator

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Osidetiger sells refurbished, flow-matched, 12-hole Densos for $190/set:

 
Been whittling away at the wiring. Truck actually ran pretty decent today, enough to take it for a wash. Went to bolt the ECU up when I got home and it immediately died while it was running. Found a few terminals at the ECU that were loose and weren't making good connection with the ECU terminals, guess 29 years will do that. Bent the inner tangs back in on a handful of terminals, mainly AFM, battery, and ground related. Only remaining code is 24, for IAT signal.
Both ends of the IAT wire have good connection, and the wire has no weird resistance values. Might need to do a voltage drop to be sure. Also double checked the values from the AFM and all are within spec.
I'm also slightly convinced I still have some gremlins going on around the ECU connectors. Will have to dive into that.
Went from having a running driving Cruiser back to running like dog all in a day🤦🏻‍♂️

hopes=crushed 😂😂😂

I'd hate to have to find a replacement harness as I literally just went through mine (clearly not thoroughly enough) and replaced all the engine connectors/corresponding terminals/wire seals...
 
Currently it will start up, run really poor, and die on it's own regardless of throttle input.
Jumping B+ to FP doesn't change anything (just to rule out the AFM wasn't killing my fuel)

The issue is also intermittent, sometimes it starts up and purrs like a kitten.
I've done a lot thus far and haven't replaced anything without good reason as to not be throwing parts at it. It seems in searching for my problem I've come across a hundred other problems that certainly weren't helping.
For myself and possibly anyone in the future reading through this, to summarize what I've done up to this point;
Initial issue
-Car would bog under load, and only accelerate up to 20% throttle input. Anything beyond that it would misfire, bog down, and backfire as if it was running super rich
-Codes 24, 32, and 41
-Tested TPS, was out of spec
Replaced with OEM Toyota TPS and adjusted via FSM (numerous times to ensure it was perfect)
-Tested AFM, was out of spec
Replaced with eBay reman unit, which bench tests within specs. Read some wary posts about the eBay units so keeping that in mind still
-Car still ran poor and nothing changed
-Tested wiring from TPS and AFM to ECU, all good
-Decided to pull engine harness for a proper inspection
95% of the connectors had broken tangs and super brittle (I'd been leaving them plugged in with hopes and dreams ;). )
-Upon removal, the rear knock connector was completely disintegrated, and the wire was broken. Also most of the FI wires were super brittle and had parts exposed.
- went through the harness, replacing any brittle/broken wires, replaced all connectors/terminals/wire seals EXCEPT for the ECU terminals. I spent hours researching what parts I needed and thought they were the same terminals as the engine connectors, they were not. Those wires aren't subject to the same conditions as the engine connectors are and were all still in good shape. I used motorsport butt connectors for any splices, including splicing the FI wires to the ECU terminals (because i didn't have those terminals and didn't care to spend hours to find what I needed and wait for shipping).
-new harness installed
-still runs like doody
-Fuel system was last gone through like, 6 years ago. There was no change when unhooking the FPR from vacuum and I knew I should go through it all as normal maintenance.
-replaced FP, filter, and regulator.
-filter was totally full of crap
-no change in running, although didn't really expect there to be
-found injectors 1+2 weren't firing. Ordered the 4-hole Bosch injector set from CruiserParts preemptively, under the thought that 1+2 were bad (I've had to replace injectors before and figured it to be a good time to replace all of them with new)
-pins #10 #20 on ECU had loose connection, probably from me sticking my testing pin into them to check circuits as well as age. Pressed the inner tang in to have good contact w/ ECU and all injectors functioned normally
-truck runs smooth, took it for a wash and when I got home, I went to bolt the ECU in and the truck died. Found a number of other terminals had loose connection as well. The problem child here was the MRel terminal (power supply for Main Relay).
-now the issue is an intermittent gremlin. Sometimes the truck runs smooth, sometimes it's so poor it can barely make it up the driveway. The only thing changing between running good and bad is the wiring near the ECU which leads me to believe I still have an issue somewhere there.
-ive checked every pin for good contact, and I've metered the entire fuel injector circuit, TPS circuit, and AFM circuit and it all tests good. Have even quadruple checked them.
-I tested each electrical output/input of each ECU pin via FSM, and all was good, come to find out this was while it was intermittenly running well, so need to go back when it's experiencing the issue

Want to add, under GOOD conditions, on startup, it has a funky idle for about ten seconds which goes away with revving and also on its own. Like 10 seconds of it not knowing what it wants to do then smooths out.
Might be related to initial closed loop switching to open loop, or possibly related to the issue I'm chasing. Also possibly my O2 sensors as they've been on the truck for a while, although they test (resistance, not via analog test on the diag port) within spec.

Currently it's running pretty rich, evident by the spark plugs being covered in black soot

The only thing I have left to do is redo the ECU pin out tests under poor running conditions. Outside of that I'm about ready to throw in the towel as I don't have the necessary time I need to get deeper into this. I know a good Automotive electrical shop locally (the owner was my electrical instructor a few years back) and might take it there if the pinout test doesn't show anything. I'm a full time mech. engineering student and need to be focusing 95% of my time on studies, not on my Land Cruiser😂😂

I'd also like to find someone locally who'd be willing to let me try their known good AFM, just to double-ensure the eBay reman one isn't secretly bad. I've heard some poor things about them, mainly bench testing good but actually being the contrary
 
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Bucked up today and hammered out the last of anything I had left to check. Figured there's no good reason to run around in circles chasing wiring, and instead look at things I haven't considered yet.
Pulled the valve cover to inspect timing alignment (reasoning was the truck smoothed out with ignition all the way advanced, so figured I'd check in case the chain jumped a tooth or something. It's been a few years since I last stuck my face under there anyhow) and also wanted to verify the distributor was lined up correctly, as I had taken it off to replace the O-ring while the battery was out 2 weeks ago. Everything in those regards was mint.

Went through and tested every electrical output from the pins on the ECU so I could see everything I had going on, following the tests from the FSM.

I had weird readings from the oxygen sensors at VF1 and VF1

Although my Oxygen sensors passed the resistance test, they were not seemingly sending signal voltage to the ECU (VF1 AND VF2 TO E1).

The procedure to test the O2s requires an analog voltmeter to monitor voltage fluctuations while warmed up and idling. Went and got the analog voltmeter from Home Depot, and started the Cruiser up. In cold running conditions, it's pretty rough, low rpms, and misfires. However it stayed running so I just let it idle and warm up while I looked through wiring schematics and diagnostic tables.
Once warm, it kept surging for a minute and smoothed itself out. Freely revved, and didn't have any signs of a misfire (outside of needing a tune up, but saving that for AFTER it's properly fixed).

I verified that NEITHER O2 was sending signal to the ECU, although both are receiving voltage at their respective +B terminals, and I went as far as to test every circuit involving the O2s just to be 110% sure.

Currently have a TPS code. Swapped it out the other night with a known good (new) spare I had just for sh*ts n giggles, adjusted the kick down cable to spec while i had the TB off (there was slack in the cable), and made sure numerous times that everything regarding the TPS worked as it should.

The fact I'm throwing a TPS signal code for O2s is unsettling, but it is OBD1. Sensors are probably telling the ECU it's getting a ton of air, and the ECU is going super rich, which would make sense. But I'd like to have an understanding of why these old school ECUs would throw a code unrelated to my issue. Why wouldn't I have an O2 code?

With the (bad) O2s fully warmed up, I was actually able to take it on the highway, get gas, and fix a random pedestrian's car at the gas station. Didn't skip a beat. Although it's definitely missing power and still on the rich side.

Went with the Bosch 15728 sensors. There's a whole thread on them by SUMOTOY O2 Sensor Replacement - 1994 FZJ80 - https://forum.ih8mud.com/threads/o2-sensor-replacement-1994-fzj80.118555/

Figured I'd be better off which the newer style technology that's less likely to succumb to fouling and more accurate than our older style O2s, also $100 for a pair? Deal.

O2s and tune up parts get here Thursday, just in time for my camping trip this weekend😂

If I'm being honest, at this point I've fixed a handful of issues through this whole endeavor. Obviously my Cruiser needed a proper, PROPER, going through. I can't say for certain what the original issue was, for all I know the O2s could've fouled while the engine ran like booty hole during this whole diagnostic.
I'll report back with an update after I've installed the new oxygen sensors.

Might just go to show, don't overlook the simple stuff. I'm not holding my breath though, it ain't over till the fat lady sings!

Honestly from here on out, I'm probably just going to test the ECU values any time I get a code if it's not a quick fix. An hour of poking around with a multimeter could have saved me a lottttt of headache. Then again, everything else I've fixed a long the way could have easily caused the same issues too so🤷🏻‍♂️🤷🏻‍♂️
 
Had a good buddy come by and give me a hand with my 80. The Bosch O2s came in from RockAuto, but one was wrong. After that I'm done buying anything from RockAuto, not sure what happened, they used to be really good.
Got a set of OEM O2s from Oreilly's and installed them with new spark plugs which didn't solve the issue.
If you don't wanna read the story, the upgraded 4-port injectors I got were absolutely dumping fuel. Slapping the old injectors back in solved the issue. It runs rough on cold starts but once it's warmed up it's so smooooth!

My buddy (Jeff) and I started from square 1 for the diag.
Had codes for ECT and IAT
Started by ruling out mechanical issues;
Leak down was 8-10% across all cylinders (way easier to do with 2 people. Also, quite impressed by my 300K+ engine!) -good
Pessurized smoke test (@ 10psi) showed a vacuum leak from the intake boot, taped the crap outta it and went on. -kind of expected
Hooked the AFM to the throttle body with a silicone coupler just to 100% rule out the rubber tube -no change
Found the new NGK ECT had a resistance of 1500 ohms (yikes) -bad
replaced with a new unit from the parts store -better, but far from perfect
Metered ECT wiring to ECU -good
after the ECT swap and vacuum bleeding the coolant system, the truck definitely ran better but was still super rich
We went on to meter all the wiring for the fuel system;
AFM, COR, FP relay, FP, ECU, Injectors etc etc) -good
Tested fuel pressure w/o engine running; 44 psi -good
Fuel pressure w/ engine running; 38 psi -good
We also did a baseline while running with the regulator vacuum unhooked, dont recall the value but it was fine -good

After that we tested the O2 circuit to the ECU (with new O2s installed) -good
Metered AFM to ECU -good
Metered TPS to ECU -good
Tested TPS sensor adjustment -good
Bench tested IACV function -good
Swapped ECU -no change

At this point we had gone through everything that made the engine run and were both totally perplexed.
The only thing left to do was swap the new Bosch 4-hole injectors I installed with the old original injectors. If it wasn't that, we would've had nothing left to try.

To our amazement and relief, she fired right up! Had a bit of a misfire when cold but once warm it smoothed out

SOOOOOOO I most likely fixed my problem a while ago, but in installing the new injectors, I introduced a new issue.
I'm in talks with the company I bought them from to figure out why they made the truck so rich, in theory the only difference is the spray pattern.
These things happen though, I'm glad to have customer service backing them unlike literally anything I bought from RockAuto

I'll be working to figure out why I have a cold start issue. Other than having to warm the truck up before driving, it runs great!!
 
Had a good buddy come by and give me a hand with my 80. The Bosch O2s came in from RockAuto, but one was wrong. After that I'm done buying anything from RockAuto, not sure what happened, they used to be really good.
Got a set of OEM O2s from Oreilly's and installed them with new spark plugs which didn't solve the issue.
If you don't wanna read the story, the upgraded 4-port injectors I got were absolutely dumping fuel. Slapping the old injectors back in solved the issue. It runs rough on cold starts but once it's warmed up it's so smooooth!

My buddy (Jeff) and I started from square 1 for the diag.
Had codes for ECT and IAT
Started by ruling out mechanical issues;
Leak down was 8-10% across all cylinders (way easier to do with 2 people. Also, quite impressed by my 300K+ engine!) -good
Pessurized smoke test (@ 10psi) showed a vacuum leak from the intake boot, taped the crap outta it and went on. -kind of expected
Hooked the AFM to the throttle body with a silicone coupler just to 100% rule out the rubber tube -no change
Found the new NGK ECT had a resistance of 1500 ohms (yikes) -bad
replaced with a new unit from the parts store -better, but far from perfect
Metered ECT wiring to ECU -good
after the ECT swap and vacuum bleeding the coolant system, the truck definitely ran better but was still super rich
We went on to meter all the wiring for the fuel system;
AFM, COR, FP relay, FP, ECU, Injectors etc etc) -good
Tested fuel pressure w/o engine running; 44 psi -good
Fuel pressure w/ engine running; 38 psi -good
We also did a baseline while running with the regulator vacuum unhooked, dont recall the value but it was fine -good

After that we tested the O2 circuit to the ECU (with new O2s installed) -good
Metered AFM to ECU -good
Metered TPS to ECU -good
Tested TPS sensor adjustment -good
Bench tested IACV function -good
Swapped ECU -no change

At this point we had gone through everything that made the engine run and were both totally perplexed.
The only thing left to do was swap the new Bosch 4-hole injectors I installed with the old original injectors. If it wasn't that, we would've had nothing left to try.

To our amazement and relief, she fired right up! Had a bit of a misfire when cold but once warm it smoothed out

SOOOOOOO I most likely fixed my problem a while ago, but in installing the new injectors, I introduced a new issue.
I'm in talks with the company I bought them from to figure out why they made the truck so rich, in theory the only difference is the spray pattern.
These things happen though, I'm glad to have customer service backing them unlike literally anything I bought from RockAuto

I'll be working to figure out why I have a cold start issue. Other than having to warm the truck up before driving, it runs great!!
Way to endure. I think I mentioned- my problems also started after swapping to 12 hole injectors. Powerless, pulling timing, crap mileage. Runs fairly smooth. I may swap the old ones back in too (after servicing them)

Thanks for all of your updates.
 
Way to endure. I think I mentioned- my problems also started after swapping to 12 hole injectors. Powerless, pulling timing, crap mileage. Runs fairly smooth. I may swap the old ones back in too (after servicing them)

Thanks for all of your updates.
I would love to be able to upgrade the injectors, I mean as long as they flow the same volumetric rate over a certain time as the OEM ones it should work in theory. The fuel pressure regulator controls fuel pressure in the system and the pump simply feeds fuel.
It's possible if the injectors flow too much that an adjustable FPR could be used to turn them down. That would also require an air:fuel wideband sensor/gauge to get it dialed in
 
So regarding the cold start;
Pulled codes 83, 84, 85 for TCM Communication 😅

These codes are well documented to exert the symptoms I'm experiencing, and is repaired by installing the later model ECU as there was a recall.
I believe I already have the later model but I'll have to check. I have 3 ECUs in total (don't ask me why. I have no clue where the third came from😂😂)
So if anything I'll do the old switcheroo and see what sticks

Never ends I guess! 🤪
 
So regarding the cold start;
Pulled codes 83, 84, 85 for TCM Communication 😅

These codes are well documented to exert the symptoms I'm experiencing, and is repaired by installing the later model ECU as there was a recall.
I believe I already have the later model but I'll have to check. I have 3 ECUs in total (don't ask me why. I have no clue where the third came from😂😂)
So if anything I'll do the old switcheroo and see what sticks

Never ends I guess! 🤪
Mine normally runs on propane, but a few years ago when ide switch over to petrol it ran rough, misfires etc. Threw the parts cannon at it but cleaning the oem injectors fixed it.

Recently had a problem with my 3rzfe, started misfiring on cold start up. Smoothed out after 15 seconds of 1800rpm and then drove beautifully. Turned out to be a cracked head, #2 inlet port.

After shutdown pressurised coolant would trickle down into #2, get a nice pool on top of piston. in morning cold start up coolant would foul the plug for 15 seconds until it cleared out. I thought that may be your issue for a while there.
 
Mine normally runs on propane, but a few years ago when ide switch over to petrol it ran rough, misfires etc. Threw the parts cannon at it but cleaning the oem injectors fixed it.

Recently had a problem with my 3rzfe, started misfiring on cold start up. Smoothed out after 15 seconds of 1800rpm and then drove beautifully. Turned out to be a cracked head, #2 inlet port.

After shutdown pressurised coolant would trickle down into #2, get a nice pool on top of piston. in morning cold start up coolant would foul the plug for 15 seconds until it cleared out. I thought that may be your issue for a while there.
What sort of mileage do you get with propane??

And the thought about coolant getting in definitely crossed my mind. It still wouldn't be a bad idea to rebuild my head, but at that point I'd rather put the money towards an engine swap
 
Previous discussion on injectors, FWIW

 
Previous discussion on injectors, FWIW

I was really excited for these, I'm not sure why I had such extreme issues with them. In all the pictures I've seen they're orange/brown colored whereas the ones I received were black. Manufacturers usually color code injectors, but I also might be overthinking it.
I'm just out here wanting that extra 1mpg wherever I can get it🤪
LS swap would get 20 mpg🤔
 
What sort of mileage do you get with propane??

And the thought about coolant getting in definitely crossed my mind. It still wouldn't be a bad idea to rebuild my head, but at that point I'd rather put the money towards an engine swap
I get about 380km from 85L of propane (LPG). i see a lot of other 80 LPG users quote 420/440km, ive never got that.

Still thirsty but LPG (propane) about half the cost of Petrol here. Great for city use, totally useless for outback overlanding. Cant refill at temps above 38 deg C and as such not many outback outlets stock it.

I didn't convert to MPG for you, it all gets too hard as an imperial (god save the queen) gallon is 4.5L, whilst one of yours is only 3.8.

Notice i didnt refer to "GAS".

Where i live GAS is a Vapour product such Butane, Propane, LPG, acetylene, oxygen etc.

You guys refer to a liquid product (gasolene) and call it a GAS. I dont get it.
 
@BakerFJ nice job amigo, a really detailed and methodical way of approaching your issues. I also like the way you write and emphasize as it totally works with my mind.

I'll just sit back and not be an armchair Qback! :popcorn:
 
I get about 380km from 85L of propane (LPG). i see a lot of other 80 LPG users quote 420/440km, ive never got that.

Still thirsty but LPG (propane) about half the cost of Petrol here. Great for city use, totally useless for outback overlanding. Cant refill at temps above 38 deg C and as such not many outback outlets stock it.

I didn't convert to MPG for you, it all gets too hard as an imperial (god save the queen) gallon is 4.5L, whilst one of yours is only 3.8.

Notice i didnt refer to "GAS".

Where i live GAS is a Vapour product such Butane, Propane, LPG, acetylene, oxygen etc.

You guys refer to a liquid product (gasolene) and call it a GAS. I dont get it.
Ha no worries on the conversion, I'm an engineering student and do everything in metric anyways. Good point on the gas, I mean FUEL. And football? You mean pass and clash?😂
 
Swapped ECUs the other morning and took a look at the P/Ns
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Peep the parachute pants. The swag is real

60170 is the original ECU to the truck, and is known to eventually have issues (which is included in a recall) with TCM Communication codes. Haven't had this one installed in years. The 60221 is the updated ECU (end of 1994) which is supposed to remedy this issue. I've had the 60221 installed for a long time and it was the one experiencing the TCM communication codes, so not entirely sure what's going on there yet. The only thing I've changed in respect to the tranny is the kick-down cable on the throttle body, but I just tightened it back to spec so that shouldn't cause any qualms.

I did swap in the other 60221 ECU the other morning while it was idling like bootyhole and it seemingly got worse. Swapped back to the one that was in before.
However, I have multiple issues still going on (like the intake vacuum leak).

To be frank, I should focus on the other mechanical issues before tackling TCM codes, otherwise I'll get caught up in chasing stuff.
The cold start issue of misfiring/stalling/low idle I've found is remedied by holding 1500 rpm until the engine is properly warmed up, and then some. Even then, it'll still be down on power and retain a slight misfire until I eventually pull off into a parking lot and fiddle with crap on the engine.
It's NOT related to ignition as all those components are new. Except the coil, but that would be an awful misfire.
I haven't replaced my cracked intake tube (new one arrives Saturday, $17 on Amazon.....I'll probably get what I pay for but F it)
It's funny, on my current intake tube the crack is on the very end where it mates to the throttle body. I've rtv'ed, tessa taped, rtv'ed, and taped again lol
This morning I moved the wire intake clamp to sit over the TB lip with the intention of sealing the tube before the crack, rather than on the crack. Engine smoothed out immediately----could just be a fluke though. I'll cold start it after studying here at UT in a few hours and see what happens. I've found the misfire remedies itself randomly

Installed a used roof rack/awning combo I scored off FB Marketplace. It's like rewarding yourself with an M&M. Been almost single-handedly my motivation to get the rig running. Ignore my jank hood, got a crack in the structure and the new struts force it up on the side. Anyone have a hood near ATX? I'm interested lol
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The 270 degree awning is freakin' sweet. Need to find a new vinyl bag for it, the zipper is falling off and it's like a tent bag---almost impossible to get back on hahaha. Might find a new bag or repair this one, put my highschool Home-Ec training to good use
 
Just cold started--no extreme misfiring/low idle as before. Still a slight misfire though.
Half tempted to install an air/fuel ratio gauge. Thought it'd be cool to integrate a digital display into the OEM clock. My clock doesn't work currently anyways, just got a sticker on it that says MPG:ASS 😂😂

As a racecar mechanic, most of the diag we face is remedied with a "what's changed from point A to point B" mindset. With that, it doesn't make sense for my ECU to be causing the TCM codes, especially since I can swap it with another and nothing changes. Highlllyyyy unlikely to have multiple bad ECUs, especially the updated ones at that.
This brings me to the thought I had while driving home--
I had the transmission connectors (by the starter) disconnected when I pulled the throttle body while doing my diagnosis. Some coolant got into the connections and I was out of brake cleaner to clear it out so I just sent it. I've read that the 80 can connectors get cranky when wet, so gonna disconnect them and clean them out, see if anything changes. It definitely would make sense since I didn't have TCM codes before, and I haven't replaced/altered anything regarding the transmission
 

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