YJ Build: to OBD-II or not to OBD-II?

[Root Moose]

Sorry to toss out the proverbial wrench toting tree swinger but I think there is one area you will need to address.
The Speedo/dash.
You will likely find it easier (maybe?) to just buy (craigslist/ebay/junkyard?) an entire, complete dash from a 9....uh, 3? or newer YJ. IIRC, the speedo was changed around 91-92 to a much different style. They look similar but don't interchange and IIRC the speedo interacts with the OBD system...? I may be off but I swear I delt something along those lines with my 91...

Ok, this is something I will have to research. Thanks.

I was toying with doing aftermarket gauges as part of an interior "update". If I spend money on OEM stuff then maybe it makes sense to spend a bit more for more modern looking aftermarket gauges.

 

[fiddy]

Yes, as pictured the 97+XJs use a cast aluminum sub frame that bolts to the lower "A" pillar/inner fender as well as to cowl at the top. The XJ firewall/cowl has brackets and studs that are used to locate and mount the top 2 bolts of the sub frame. This is not the case on the MJ, so I drilled holes straight through the cowl into the wiper motor comparment and used large fender washers to set the spacing.

I this pic you can see how the XJ firewall/cowl has the spacers and studs built in for the sub frame.

The aluminum strip I was referring too was used for the tabs that the actual dash uses to mount to the tabs that are on the MJ below the windshield.

Not to go back off topic again, but do you have a link to your build?

**edit** found it.

 

[fin reaper]

Pulling up an old post here: I'm in the same boat - I've got a line on a '96 5.2L Magnum OBD-II, but I'm scratching my head on what to do with the gauges and fuel system for my '88 YJ. I like the fuel cell ring idea.

Any updates or discoveries on the gauge side? I'd like to keep OEM YJ gauges if possible (i.e. 93-95 vintage).

Ok, this is something I will have to research. Thanks.

I was toying with doing aftermarket gauges as part of an interior "update". If I spend money on OEM stuff then maybe it makes sense to spend a bit more for more modern looking aftermarket gauges.

 

[Root Moose]

I've changed directions and am doing an MJ build currently. The frame I had put aside for the YJ turned out to be soft in all the classic places once I turned my attention to it (i.e started wailing on it with a bodyman's hammer) and then the cold weather set in so I've started building what I already have on hand instead.

From what I remember the only sticky point is the OBD-II vs OBD-I speedometer.

There is a specific year VSS/Speedo assembly that fits in the YJ NV231 that has both a mechanical drive and a VSS signal coming out of it. IIRC it is `91 but google it to confirm. The rest of the gauges are not a big deal - worst case change the sending units. This will let you keep your MY88 gauges.

If you want to get some 93-95 gauges everything should work with minimal issues as the speedo will already be set up for the VSS signal from your ZJ (Dak?) drivetrain. You might have to change out the sending unit for a different year, I dunno.

There's lots of information on this on the Jeep forums. It takes a little while to ferret it out though because the search terms bring up a lot of noise.

HTH