OBD1 is the first generation onboard diagnostics, which is what the renix is. I do apologize to everyone if it is not the correct term. I use it as a generic term for all computer systems that are pre OBDII

No one works on renix systems anymore. There are not enough of them around. The Jeep shop I took it too has a lot of experience with them.

 

Renix also only gives live data.

 

Try this.

while cranking, squeeze this relay.

 

I replaced that relay before I took it to the shop. The start signal was getting back to the ECU from this relay though.

 

Cjjcalhoun: Im gonna throw this one out there as well. Wasn't on my Renix but on one of my BMW E21's. The thing wouldn't crank and we couldn't figure it out. It was sitting outside my garage while I worked on my other BMW's and one day as I was staring at it I noticed a tiny piece of dog food on the ground. It turned out to be a mouse storing a bunch of food in my exhaust system. Cleared it out and it fired up. I know it's unlikely, but if we're going to outer space with possibilities, it's worth a mention.

Cruiser: Ah yes! Long story short, my leafs were sagging and I randomly asked Cruiser for a shop recommendation. He ended up inviting me to his house and helping me do the job. We tried getting new springs, but that didn't work out so we put on some helper springs that he had laying around. Those things got us through a majority of the 19,000 miles we put on Uncle Jess during our trip. He also gave me an introduction to @BassLicks who helped us out big time while we were down in the Sunshine State. The community on here is ****ing phenomenal and full of great people!

 

o.k., I just read the entire thread, its getting late and I am kind of rummy, but I do not see any reference to pulling the plugs and doing a compression check, or seeing if the plugs are getting wet with fuel or something like that. If the cam chain let go it wouldn't turn the distributor, etc. etc. Just thinking out loud. Hope you get it running.

 

Good idea with the timing chain, no one has brought it up yet.

I have watched the distributor turn while setting the timing. I have done a compression check, and my injectors are not firing either. Good ideas though.

 

Just to be correct, RENIX predates OBDI. OBDI was the standard on-board diagnostic system from 1991 onwards. Jeeps of 1986-1990 used the RENIX system.

The Snap-On MT2500 can read the RENIX fuel related parameters being sent to the ECU like fuel trim, pulse width, TPS values, O2 etc. I bought my MT-2500 off a Snap-on guy for $200. It can read RENIX, OBDI, OBDII and others up to 1999. A lot of garages still have them. Might have to ask.

There's a few youtube videos of guys using the MT-2500 on Renix Jeeps.

 

How about this cool alternative. Very affordable:

http://cruiser54.com/?p=568

 

Yes-I've been watching that guy's inventions. Would be great but only works on the Renix. The Snap-on works on other cars (and I've got a few too many!).

 

I see you have a few OBD2 cars, one Renix, and one that's probably non computer. So get the cheap Renix thing and a cheap OBD2 and you're done.

 

Hey, that helpfulness isn't limited to the Renix crowd either! Sure, it's his specialty, but I've certainly learned a **** TON about the process of troubleshooting from Cruiser. It's a helluva lot easier to go through the process of T&D, narrow it down to a few possible causes, and go from there than it is to just start replacing parts at random and still end up with the same results.

Aw shucks, I didn't help ya out that much.. just gave you a disheveled, cat-infested garage and a cluttered workbench on which to work... although our "Harbor Freight vice science experiment" was still highly successful in my book. I've never seen such a marvelous failure in my life!

 

I got the Jeep back and it is running. Long story short, it was the ICM. I had already replaced this but bad information from the manual left me stuck troubleshooting the ECU. The manual says that the ECU should put out a 5v square wave signal for spark, which is not correct. The ECU actually puts out a 5v sine wave signal, which is what mine was doing. The mechanic I took it to was scratching his head at this also, which cost me a lot of money. He ended up just swapping parts from a MJ he had that was running. I could kick my self now for getting hung up on that one signal. Either way, it is running now - anyone want to purchase a Cherokee?

A huge THANK YOU to everyone for helping me all that you could!

 

Hey glad to see you got it up and running!

 

Noice dude!