GonzoTheGreat

X2. This has worked great for me. yes. The whole column is attached to two studs, one on each side. Loosen both nuts so there are just a couple threads remaining, and the whole column drops a little. Then pull the dash bezel straight out. You still might have to squeeze it a little, but you shouldn’t have to force anything.

Is the little vacuum line that runs from the other port on the valve cover clean and free-flowing? That’s the one that is meant to draw blow-by to the intake. If it’s clogged, cracked, or disconnected, it can cause this. also what oil do you run? I would imagine a thinner oil would actually increase blow-by.

5 on 4.5” is the lug stud pattern on the hub. 1/2” x 20 is the stud/nut thread NAPA

If there’s an exhaust manifold leak, there is likely an intake manifold leak, ie a vacuum leak. Both manifolds share the same mounting bolts. Have you checked all of the manifold bolts and studs to make sure they are in, and tight?

I know they’re not super common, but if anyone has one of these covers and/or the two retainer clips, and would be willing to ship to MA, please let me know. Thanks!

I was told this is an ‘86, and it has the 86 hood prop, but the VIN seems to be an 87 VIN, so I’m guessing either early ‘87, or the dash was swapped. Please move this if it’s in the wrong place. This truck is just outside of San Jose Costa Rica, in the shop of Danilo Papas, the resident Renix guru, and owner of many many jeep vehicles. He has had this MJ for 25 years. It has full WJ brakes and axles, a block from a late model 2.5 XJ converted to TBI LPG. Several small mods like late XJ mirrors, and I didn’t see it, but he says there is an OEM sport bar in the back of the shop that’s going into this one.

Thanks @pizzaman09! Ok. So, problem solved. This was not a Comanche specific problem, or anything renix, or even electrical. Just basic mechanics. Compression passed the thumb-on-the-spark-plug-hole test, but leaving it parked for 11 months allowed the rings to dry out, and it wouldn’t hold enough compression for combustion. With enough jumping, cranking, and feathering the throttle, it came back to life. Good to know all my electrical testing was accurate at least I’ll add a little more detail in my road trip thread (which fortunately, is back on track). But long story short I met a super cool Costa Rican dude with all the renix parts and knowledge you could ask for. It was good to talk through the situation with a knowledgeable person, even despite a language barrier.

Ok that’s something to note on a running engine, but it doesn’t really help with a no-start condition. I’m starting to go a little crazy here. I’ve rechecked and recleaned my engine-chassis-battery grounds. I’ve rechecked every sensor, and they’re all giving proper resistances and voltages. I’ve rechecked for fuel and spark, and it’s there. I’m still trying to find a timing light and pressure gauge just to be 100% sure I have the right amount of each. Hopefully that will happen tomorrow. Stuff is a little tricky to find here. 🇨🇷 I have now swapped in a known-good, oem ICM and coil, and a known-good, oem ECU. the only part of the ignition system I haven’t been able to find locally is the distributor cap. It’s pretty new, so there’s not much to go bad there, but I checked it anyway. I get about 30ohms between the center post on the outside and the spring-loaded contact on the inside. I didn’t expect to find any resistance there. Can someone with a good dizzy cap check that number? If I push the spring down all the way with the meter probe, it drops to about 3ohms.

My bad. I had my values reversed. I checked again and it’s 4.7V at WOT and around 1V closed. I think it would settle to the correct .8v if the ISA were retracted. Again though, I don’t think this would be a crank, no-start if it were just a little off. As I understand it, you can even run the engine with the TPS unplugged, it just doesn’t run well. I'm wondering if either the ICM or ECU is screwing up the timing advance. I am still trying to find a timing light I can borrow, but I did check the rotor at TDC cyl1, and it’s just past the cyl1 pickup in the cap, which I understand to be the correct location, then 3,4,2 to follow.

Yeah, It cranks over like normal. The only thing I did was park it. It ran fine when parked. I can’t imagine it would lose compression or timing from just sitting, but I’m trying to track down a compression tester just in case. I’m quite a ways from home, and a bit limited on tools, but where there’s a will there’s a way. And again, I don’t see how timing would change from just sitting, but if there was a problem with that, it could explain why I have fuel and spark, but no combustion. I put a new coil/plugs/wires/and rotor in today. New cap arrives Monday. Still no change, and yes both the old and new wires were installed correctly. I don’t have a timing light with me, but I may be able to borrow one. I just don’t know how it could have changed at all from just sitting parked. And that’s a solid 7.1 ohms on the connector pins.

I saw a lot of numbers today. It might have been 7 or .7 with my meter on the wrong scale. I'll double check that in the morning. ST and LT are both 128 squeaky clean. Both the pins on the bottom of the coil, and the connectors to the ICM. I had cleaned and greased them with dielectric in the past, and it looks like it held up. Good springiness on the ICM contacts as well. I've cleaned every connector within the last 2 years, and done all the cruiser tips btw. Forgot to mention that in the first post. I've added new grounds where recommended, including replacing the ribbon to the firewall with a new cable, extra fuel pump ground, clean ground behind tail light, etc.

I have an '89 2.5L TBI, auto tranny, 2WD Comanche After being parked for quite some time, the engine cranks over no problem, but it will not fire. I have watched the fuel pulsing from the injector. I have seen spark at each cylinder. I checked every sensor that I have that corresponds with this site. All values were within the specs listed there (except the TPS which I believe is different for four cylinders. There, I have just under 5v signal at closed, and if I recall it was just under 2v at WOT, which I believe is ok, but I also don't think I'd get a crank, no-start from a problem here). The only sensor related thing I wasn't sure about was the O2 sensor. I have .7ohms across the heater wire, but I don't know how to test it otherwise. I have an REM, and it's reading 0.02-0.04v on the O2 and air/fuel is 13.4. I don't recall what it read while starting when everything worked, so I don't know if these values are good, but I also don't believe that would prevent the engine from firing at all, if there were a problem. I've tried splashing fresh gas down the throttle, thinking maybe the tank fuel is old, but I didn't even get a sputter. Ether also did not cause it to fire, but after I aired out the manifold and unplugged the injector, I could get a little cough with ether, but no proper firing. I know very little about these injectors, but from what I've read in various threads on here, the injector seems to be doing what it's supposed to, and not doing anything it isn't supposed to. I would like to check fuel pressure, but I don't have a way to do that at the moment. It sprays out pretty strong when I disconnect a line though. My only remaining thought is that the spark is too weak. I checked spark by holding the plugs to the block, and it was there each time, but it didn't really fry my hand through the boot like I've felt in the past. I know that's not a good metric, but I'm running out of things to check. I'm trying to track down new plugs/wires/cap/rotor/coil just to rule that out, although none of them are more than 2 years old. It is however extremely hot and humid where the truck was stored and there was a little corrosion on one contact in the dizzy cap, which I've now cleaned up, and the coil has some surface rust. The engine cranks strong, but for the life of me I can hardly get it to cough just a little, let alone fire on all cylinders. I have to put down the tools and do some head scratching now, so if anyone has any input, there's probably something obvious I'm neglecting, and I'd love for anyone to point that out. TLDR: Air/fuel/spark-ok. No bang-bang.

They are most definitely fusible links. I've always kind of wanted to identify the amp ratings and change them out for blade fuses, but at the same time, they've worked for 35 years, why mess with them? yours apparently decided it wants to be messed with. If there's someone on here with an electrical manual that can ID the amperage, you should be good to just get rid of it and use a fuse.

I know he was active when he listed the wheels because I actually bought them. Sorry. He probably just hasn’t signed in recently.

How are the sway bar links looking? track bar bushing and joint ok?

Check the track bar. Any play in the joint, the bushing, or the axle-side mounting hole will cause shimmies and wobbles. Remove an end and give it a thorough inspection. You won’t always see play in the ends if it’s still in the vehicle and under load.

I think that’s the vacuum actuator near your right knee when you’re in the driver seat, that opens the middle vents. I was able to get the arm back onto the actuator in the girlfriends XJ without pulling the dash. I think I pulled the lower dash though, for visibility. I remember it was quite unpleasant to access, but easier than pulling the whole dash.

Also, pro tip, let the engine cool before you open anything.

I second the ratchet strap. I trust the factory cable only so much. Stuff whatever size tire you can fit under there, but use a ratchet strap for cheap security. for the floors, it won’t really affect the interior either way. XJ floors can be made to work, but don’t perfectly match the stiffeners in the “frame” underneath. I used the old key parts pans and had to modify slightly. They now have their MJ specific ones, and I haven’t tried them, but they look like a good fit.

Does this mean that you removed the little pink plastic hose from the valve? because that is the vacuum line that operates the heater valve. That is what allows the flow of coolant to the heater core. You need that. I don’t remember off-hand if the valve is closed WITH or WITHOUT vacuum. I’m away from my trucks at the moment. Maybe someone else can jump in with that info. you could also have someone force the valve to change positions and see if the heater blows hot.

Contact cleaner is still readily available at most hardware stores and should be used on any connector that doesn’t look new inside. also, did you verify that all those bolts on the bottom of the exhaust manifold are tight? Or just that they exist?

I always do a thin layer of RTV as well. Not so much that it squishes out inside and pieces break off, but just enough so that the gasket is not dry. It might work just fine dry, to be fair, I’ve never tried. I would make sure it’s a good brand name gasket though, and pay close attention to torque specs. Hell, now I’m curious. Maybe I’ll try it dry next time I do one, just to see.

Those decals are sick!!! this sounds like the start of a really great build. I’m looking forward to seeing it all come together!

I found this one basically in the dead center of the island. I was not expecting to find an MJ anywhere here, but there was no missing those turbines as I was passing by. I tried to get the VIN but it was completely illegible through the windshield. I didn’t want to start checking the door sticker and core support, since I was pretty blantantly trespassing already, which I generally try to minimize in a foreign country. I’ll be here a few more weeks though, so I’m gonna try to leave a note and see if I can get the owner on here. It’s well optioned, rust free, but needs a lot of work. There are a lot of RHD TJs around here, but this is the only unibody Jeep I’ve seen, so I would imagine getting certain parts is nearly impossible. Hope to have an update for the registry soon.

That sounds like the clip slipped off. It’s a little tricky getting your fingers in there without taking everything apart. I’ve had the best luck clipping it back on the collar wherever I can, and then pushing the clip with a flat head to adjust the position.