Agreen

Finally got back to it. I had to end up pulling all the panels up and inspected the harness from C118 all the way up to the first light. I never could find a physical break, so I found an old wiring harness in a bucket in the garage and stripped a pink wire out. I ran the wire along the harness, zip tied about every 12", and tied it in at both ends with a bare crimp and heat shrink. One light works, the other had a bad bulb. It's on order, but I have light! Thanks for the help.

It's at least an 87, since it has the 4.0. You can disregard the earlier link. That is specific to the 86 comanche (and 84-86 cherokees).

First post has year and model info.

https://comancheclub.com/topic/69073-86-tach-wiring/#comment-738143 The 86 didn't come with the 4.0 as an option. You either have a 4 CYLINDER 2.5 Liter engine, a 2.8 GM V6 (like the one that was in the S10), or a 2.1 diesel engine.

That's odd. I had safelite put a windshield in for me about 7 months ago and they didn't even have to wait for one to ship. They just used a regular ol' Cherokee windshield (in my 86) and they even replaced all the clips that hold my metal trim on (at no cost). If you can't find a new one, Maybe you can cut one out of an XJ at a u-pull-it yard?

Hijack permitted for preservation purposes. I just checked that connector. I have power at the pink (pin 5) wire, nothing at the pink wire at the b pillar lights. There's obviously a break somewhere in between. So now I get to pull trim and find it. Yay. There's also a long pink/black wire tucked in along with the light, which I'm assuming would go to the dome light (if equipped)? I don't think mine came with a dome light, so I'll leave it alone.

Thank you so much! I'll have to check it when I get home from work.

... I know, I know. It's a worn out topic. 1986 XLS model I just got around to troubleshooting them. All other interior lights work, just not the b-pillar ones. That tells me the fuse is good, and that the door switch works. I figured it was an issue with the bulb or the infamous flip-up/down switch with the corroding contacts. I popped the lights out and did a quick power check with a test light. Nothing. The pink/black wire is supposed to have 12v, but it has nothing at all. Multimeter verifies 0v. Is there a connector somewhere that could be unplugged? I have searched this topic extensively, but everyone seems to be having issues with the door switches or the light fixtures. I'm just wondering if anyone knows of a connector to look for before I have to start tearing out all the interior to trace the wiring back?

Need a good 4wd AW4? I have one on the floor of my garage

Mechanical injection is easy, but it has to be primed and free of air. Crack the lines at the head loose, crank it over until fuel comes out at each one, tighten, then try starting again.

Look at your pedals. Does your clutch pedal look lower than the brake pedal? I had the same issue on mine. When I got it the clutch pedal was frozen. I, being the brute I am, stomped it. It freed up, I got it running (after sitting for several years) and drove it. Getting into gear was a normally a problem, so I had to double clutch every time I shifted. I figured the master and slave cylinders needed replacing. Commence 3 days of bleeding. 2 pints of brake fluid were used and I still never "got all the air out". The little tab on the clutch pedal likes to bend sometimes.

I don't think (could very well be wrong) that the 86 has a diag connector. It has a 2bbl 2.8 v6 and GM HEI ignition. I really REALLY appreciate everyone who gave input. I took both of my tachs to work with me last night and traced out the points at which I soldered the resistor on. I was way off. That "how to almanac" really changed the game when I found it. It showed the resistor chip internal diagram, and that the resistor between pins 4 and 10 usually go bad. Sure enough, it was open. And the first page I linked to didn't describe that. At the time, having only that to go off was difficult, and I ended up soldering the resistor across the wrong pads. So yeah! It's fixed now! Now to adjust the resistor and get my interior back together!

For future reference: http://www.howtoalmanac.com/kevin/projects/automotive/tachfixtruck.htm I still haven't gotten the tach fixed yet. I made a quick attempt a few days ago, but it was a spectacular failure. The page I just shared has info on that specific chip (apparently all it is is a bank of resistors). So with that knowledge, checking it should be a lot easier. Also, a tach from a 93 will not work, even for testing. I jumpered +12v, ground, and tach signal from the 86 dash to the 93 tach and it almost turned the engine off.

I dropped the tank today. It wasn't as bad as I expected. I got some chunky stuff out with flushes, and right now it's marinating in some CLR. I was hoping to find something with the sending unit, and I did. Man is it crusty. That might (maybe?) explain why my gas gauge goes crazy. I'll see what I can do with it before it goes back in. I also took care of the shattered corner glass. A really nice 2dr XJ donated it from the local PullAPart. So the last few things to fix after this: 1) windshield (full SC coverage will do it free) 2) Air Conditioning 3) Bleed the clutch 4) Adjust brakes 5) Go through all the grounds Not in that order, obviously.

I'll be honest. I snapped this picture while I was working on replacing the corner window, and I was kind of in a rush. The sun was going down and I plan on taking it to work tomorrow. I now regret not getting a better shot. Looking at what is there, it doesn't really seem to match. And to make it worse, the axle rations apparently supposed to be 4.10, and mine is 3.55. Explains the gutlessness I guess. That old 2.8 doesn't make much power. But! The current axle IS a D44, so that's nice. I guess it likely had a 35 originally.

I found this inside the door. They stabbed the window crank through it, but it's mostly legible.

scguy I'm down for that. I wonder how many people would show up.

A friend of mine keeps talking about how it's common for Fieros to have a bad tach filter, so I should be looking into that. Well, I don't see one on my coil which could be because it doesn't have one, it could be built into the circuit board, or it might not even have one? But that gives me hope that I can see of there's better info for a Fiero tach repair. The one in the box had PAP (Pull-A-Part) in paint pen on it. I'm guessing he pulled it and never got around to installing it because of how much disassembly goes into pulling thr instrument cluster. I think first I want to verify +12v, gnd, and the coil pulse at the cluster. I'm thinking it might have an open in the signal wire. Anyway, I have an oscilloscope so I can see if I'm getting it or not. I just wish I had a signal generator. Edit: Look what I found! http://www.fieros.de/en/articles/tach.html

Well, that's good and bad news. Looks like the power and ground for the tach is the same power and ground for all the instruments. So I know I don't have a problem there. Looks like 1 of 2 possibilities. Either I have no tach signal coming from the coil or 2 bad tachometers. Thanks for the diagram! Is that taken from the 86 FSM? I might need to go ahead and get one of those.

I'm just looking for the basic wiring from the coil to the tach. But I do have a lot of knowledge of electronics, so a simple tach such as this one shouldn't be that hard to figure out. I'm thinking it's probably another corroded connection somewhere along the lines, but what I'm finding is that the old AMC wiring diagrams are just so terrible. The FSM for my 98 XJ has beautiful diagrams with connector pinouts and everything I've ever needed. Here are some pictures of the tach I pulled. Luckily I brought it with me to work tonight. (I took those 2 nuts off the back, btw. I'm going to see what I can do with the circuit)

I have searched for a while and I keep coming up dry. I'm looking for a schematic for the 86 2.8 v6 that shows the tach wiring. I found one on Tom Collins' page, but it just shows the tach signal coming off the coil; not the tach or where all it goes through. My issue: -I bought this truck 2 weeks ago -Tach didn't work, found a replacement in an ammo box behind the seat. -I had to pull the dash bezel to fix the stero wiring hack job. -Figured that I'm almost there, might as well swap it to see if it works. -checked all the contacts and wiring behind the cluster, looks good. -Swapped it, turned the key on and it went to almost 1000 rpm without running. -Fired up and it pegged high. All other gauges still work (gas gauge is really bouncy, but is accurate if I'm stopped) That's when I started looking for wiring diagrams but I'm coming up short. Or if there's a common fix for this that I'm not finding in my google-fu, I'd love to hear it.

I wonder if that's the code for the wheels? Mine are the 10 spoke aluminum ones with black jeep logo center caps (which I still have all 4 of) I need better pictures. I only have the ones from when I pulled it out of its 5 year resting place. It also has that funky brake bias pushrod thing on the rear end as well.

Thanks eaglescout526! That's pretty cool. Any idea what the CGW package meant in 1986? I didn't think the 86 comanche was offered with an airbag option?

So after a few days of driving it with the carburetor at full capacity, I have decided that the 2.8 is complete @$$. Which is weird, because I had an extended cab short bed S10 with the same engine, and IT wasn't. So maybe it's gearing, maybe it's something else. But around here I have LOTS of hills. Every day I drive through hills. And it's miserable going full throttle in this poor guy. So 2 options I was looking at. First I figured a 4.0 swap was the key. Then I found out that the 86 wasn't set up for that swap and it's pretty involved. Not that I couldn't do it, it just doesn't seem like the juice would be worth the squeeze. Que the 2nd option. A Mopar V8 and 2wd AX15. I have a bellhousing from a 3.9 Dakota, and I can get a 2wd AX15 for a song+dance. Maybe even just the song. Seems like it could be a lot of fun. For right now, I have a few other projects to finish, so I'll just be collecting parts until the 81 J10 project is on the road.

It's 3+1. I wasn't sure which one is original. Did the leafs get replaced or did the axle? Sounds like the axle is the answer.