bigmistake

I will pull everything apart again tomorrow. Basically what I did was pull the harness apart, check the power from the truck with everything off - hooked that one to the correct wire on the radio. Then I checked the wire for power when the ignition was turned - verified it was getting power when the key was turned, but off when the key was off. The weird thing was - when turned all the way back to "LOCK" it sent power to it again.

Went through it again. Tested each wire with a multimeter and made sure I had the right ones hooked up to each other... The first couple of key cycles (before doing the radio setup) it turned off when the truck turned off. Then I did the initial setup on the radio (setting clock, etc) and it is doing the previous behavior. Weird!

Hey everyone, I had some time today, so figured I would tackle the stereo the previous owner put in. It is a Pioneer DEH-6810BT. When I pulled the unit from the dash, there were several cut wires, and a lot of them connected to things seemingly at random. I found this video: https://www.youtube.com/watch?v=kR2MO2kwFug and a diagram by Hornbrod: https://comancheclub.com/topic/48362-91-comanche-stereo-harness/ I went about connecting things up as best I could. After getting everything hooked up, I had sound out of both speakers, and the radio turned on. Great! When I turned off the truck, the radio stayed on. Not great! If I don't turn the key all the way to LOCK, I can pop off the face plate and plug it back in and the radio stays off. If I turn it all the way to LOCK, if I do the same thing, the radio turns on as soon as the faceplate is connected. Does this sound like I've got a grounding issue somewhere? Ignition not sending the correct signals to accessories? Or maybe I just botched the whole wiring more than I expected... Anyways, any thoughts are appreciated! Thanks all.

Thanks! I'm not going to lie, it has been awesome. I'm loving driving this truck!

As a follow up - looks like this was the fix! I've been driving the truck daily since Nov 15th with no hiccups. I even took it down to visit family over Thanksgiving and it handled highways great. Now that things are running smoothly, I feel more confident spending some time and money towards more fun upgrades.

Bump!

If you don't want it, and they end up not wanting it... let me know. Maybe we can figure out shipping it cross country. I really want one for my short bed.

Great video - and another OM617!!! Thanks for sharing, and keep filming. I loved it.

I don't know how I missed this build thread - I've been obsessively reading up on OM617 swaps wherever I can find them. Following along, and great work!

I just had my first real test in my 2.5L Comanche. Drove the truck home over Thanksgiving - about half a tank on the highway (going 70ish) and half around town. I got an average of 22mpg for the tank. I was pretty impressed!

The shell looks awful... you should send it to me in Texas! Seriously - looks great. Can't wait to see where the build goes!

How do you like the front bumper so far? That looks like a pretty good deal on their site right now. That dual swing out is awesome!! Loving your build so far!

@HOrnbrod - Watching this video, I realized that my '91 2.5L is maybe setup incorrectly? I see in your Autozone link that the rear port is the fresh air inlet. Mine has a "twist in" fitting with no grommet or anything rubberized at all to secure it in place. Should I look at buying a grommet + push in fitting? Or is mine okay?

I'm really not a fan of the new truck... Looks like a Hummer-wannabe-truck. Nothing seems to go together. Oh well.

I had the exact symptoms of "driving fine then stops accelerating, then randomly starts accelerating again." It ended up being an early indicator that my fuel pump was going bad.

It started right up this morning! Drove great! It is like having a new truck... Thanks everyone for all of the help!

Lots of work this week on the MJ. Replaced fuel pressure regulator, upgraded to 4 hole fuel injectors, dropped my gas tank and replaced my fuel pump. Definitely things I've never even thought about attempting on my own! All of this has been working towards fixing the stuttering, misfires, lack of acceleration, and long crank times I've been experiencing. The fuel pump took me a while (I had trouble working the tank down to the ground), but I eventually got everything back together. Took a while to start up, but eventually started and the initial test drive was really promising. I'm hoping it starts right up tomorrow and runs like a champ! Here is a photo of the new fuel pump trimmed and ready to go back in the tank:

Alright, I installed the new fuel pump and took it for a test drive. Initial drive (about 5 miles) feels like a different truck. When I first tried to start it, it cranked for a LONG time... enough that I was worried I hooked something up wrong. I couldn't hear the pump turn on when I turned the key to ON like my last one (my previous pump was really loud), so I got pretty demoralized. Cranked it for a bit longer and it fired up. Let it idle while I cleaned up the garage, then took it for a spin. Accelerates when I hit the pedal, no misfires, stutters, or bogging down. It is early for me to say "everything is fixed," but I'm feeling pretty good initially. I will know for sure when I start it up in the morning after letting it sit overnight.

I removed the parts that were obviously flaking and there was still a lot left intact, so I went ahead and re-installed it. Thanks for the information, Eagle!

I pulled my fuel pump and this rubber part is completely falling apart and flaking: Any ideas what it is and if I need a new one? Or can I just remove it? My new pump doesn't have one.

I ended up getting sick this weekend, so no time spent on the truck. Hopefully next weekend I can go rent the tools again and make some progress.

Fuel pressure regulator came in so I threw it on over lunch. It wasn't a miracle fix, but I think the engine sounded like it was running a bit better. Other parts should be trickling in over the weekend.

That is my plan! I also went ahead and ordered a set of injectors that I plan on upgrading while I'm messing with all this stuff.

Good to know! I'm at about a half tank right now... will likely drain the rest off before I do anything. I will pull the rail this weekend and take a look before swapping the pump. Thanks!

Thanks! Parts ordered!