scaleless

Haha, I guess it's just about that time! But not quite yet, it's still running like a disaster. I adjusted the TPS and had a few seconds of perfect idling. After attempting to rev the engine, it stumbled and backfired a few times, and now it's missing on at least two cylinders. I need to check a few things, but it's likely a couple of parts of unknown provenance: the coil and distributor were in a box in the truck when I bought it, and who knows if they work! I lost the CPS and I have a new aftermarket one, as well, and I know that might be an issue. I was also having issues with the injectors, and they may be damaged. Finally on the list is the exhaust manifold is not hooked to anything, and with how close the O2 sensor is to the output, it may be driving the fuel trim very rich, but I wouldn't think that would cause as bad of a miss! I hooked up my timing light just to check for spark really quick, and spark seems to be very irregular on multiple cylinders. Though this light has had problems on very short spark wires previously, so I don't know if I trust that information. Anyways, I'm having fun diagnosing today!

Okay, okay, there's a lot of work that I'm behind on posting about! But here's a little teaser: 20210621_002947_1_1_small.mp4 I forgot to properly adjust the TPS before starting so the idle is poor and it stumbles off idle, but hey, I think that's a great first start! I frankly didn't expect it to start the first time haha. I'll address the TPS and post about all the work I've done shortly.

I have used both the cloth tape and self-amalgamating tape and the self-amalgamating tape seems to hold up way better when sealing the ends of the loom. The cloth tape, at least the ones intended for use inside the engine compartment, are good for wrapping the wiring before looming. I like to wrap the wires fairly tightly before looming it, which helps keep the loom from opening up in tight bends. That all sounds exactly like what you're doing, though.

I just found a new small vacuum ball from Dorman that I had lost and it does have a check valve build into the manifold side of the ball.

He says he already checked the fuel pump ground. Also, the fuel pump ground would not affect the fuel pump relay - the relay is grounded, as Ohm said, at ECU pin 5. Relays usually buzz when they receive unstable power, which causes the coil to vibrate or even engage/disengage rapidly. My first expectation with a buzzing relay that didn't shut off would be a weak short to ground somewhere on the fuel pump relay ground wire. That doesn't explain why it dies on the road, however. If you're ok with cutting and splicing back wires, I would cut the fuel pump ground close to the ECU. If it keeps running, it's a wiring issue. If it stops buzzing, it's the ECU or connector. If there isn't a break in the wire somewhere, it's very likely that there is a failing transistor in the ECU. I find it more likely than a corroded or broken ECU connector with how they're designed, but I may be wrong.

Looks like you have no sound system! Like Pete said, if your truck came with no radio from the factory, it should have a radio delete plate on the dash.

The Renix computer outputs a serial bitstream that you can read all about on NickInTime's website. Given the data is significantly different between the 4.0 and 2.5 and the pinout of the diagnostic connector is even different, I very much doubt this application shares any similarities to either. It's simply a universal diagnostic connector that AMC used likely without any standardization.

A sad fate!

Oh yeah, don't let that fool you. Jesser's has a huge trove of AMC key blanks. Also from somewhere in the 70s Jeep keys were RA4 for the ignition and RA3 for the locks, then 1985 switched to RA5-J for the ignition and kept RA3 for the doors.

Despite being known for small engines, Briggs and Stratton was a major manufacturer of OEM and aftermarket automotive parts until they spun that segment off into Strattec in 1995. One of their most profitable ventures was ignition switches and lock cylinders, and this is a blank that would have came with a Briggs and Stratton lock cylinder for a Ford/Lincoln/Mercury vehicle. Here is another key for sale on ebay: https://www.ebay.com/itm/283860131992

Definitely available - my friend just got his Toyota Highlander reupholstered in perforated vinyl that looks a lot like the stock wheel covering.

I've been told the main harness bolt may have changed to metric over the years, but on my '87 it is definitely 1/4"

Yeah, that's the factory dielectric goop. Very gross, sticks to everything, it sucks.

Whew ok put down the tire shine and back away!

Hell yeah, I would LOVE a set!

But most do have a port where a bleed screw would go - just drill the hole and install a bleed screw. I honestly can't recall. A lot of the parts were from Crown so it may have been from them, but I'll need to reference my receipts later.

With a little paint, that'd be a beautiful truck.

I disagree - while there is no room for error, an AX15 rebuild is very straightforward and there are many instructional videos to supplement the factory service manual. Jeep_AX15_service_manual_Transmission.pdf

Renix never had an inline check valve. If you want to add one, though, it should go before the reservoir. Once you add one, put a vacuum guage on the reservoir side and see if it holds a vacuum with the engine off. If not, you have a leak that needs to be addressed. Even if you don't have a leak, test all the HVAC settings to see if you have a leak in or going to one or the vacuum actuators.

Ah, you know, that makes a lot more sense!

As said, that's an AX15, not an AX4. First gear synchro is probably toast, or worse: you're missing some teeth on the gear. Since you say it's an AX4, are you missing fifth as well? Regardless, its time for a rebuild.

No real temporary solution. The crunch in reverse is just because reverse is unsynchronized. It would be a lot worse if the slave is bad and your clutch is dragging, like your description makes it sound.

The wiring diagram colors are a crapshoot, but I think that pin supplies switched power for the blower motor. You might want to complete Cruiser's blower motor ground tip, or perhaps you might need to replace your blower motor if it's constantly drawing too much current.

Well-deserved!

Make sure they're the exact same bulb type. They can look similar but be different enough to not work e.g. have a shorter base and not make an electrical connection. Test for +12v when you're in reverse and that'll answer your question.