Ok so many of you have seen my posts for guages. Instead of deviate from my dash rip out thread, I figured I would ask a pointed question here.

Ok so I am moving forward with designing an aftermarket guage cluster and full dash setup. I keep getting a nagging question in the back of my mind, though. Is installing new and custom guages as easy as attaching the wires from the dash plug to the new guages? Do I need to get new sensors, and if so, how do I maintain data to the ECU? Do I HAVE to maintain sensor data to the ECU? Guages in question that I would be installing are tach, speedo, fuel, battery, oil, temp. I am also going to get a RENIX computer display module, which plugs into the trouble block in the engine bay.

After much consideration I am not going digital. Would be nice but analogue displays are just fine for me. I am doing all LED back lighting. I would like all water proof guages, cuz you never know lol.

Thanks in advance. I know someone out there has the advice I am seeking!

 

You have to run two data systems. One for your ECM, so don't mess with those sensors and another analogue system for the gauges. I have already done this with an engine conversion. You will have to use the sensors for the oil pressure and temp gauges for the specific gauges. You will end up drilling and taping some holes, or at least a little creative plumbing for the oil pressure gauge. If your gas gauge runs off ECM, you will need the type of pump and gauge sensor for an earlier model

 

What do you mean by that last bit? The thought that just came to mind was maybe adding a new (secondary) float and run wire to new guage.
i have also thought about just modifying the existing guage cluster plug to the new guages. Wouldn't take much to follow them on the stock circuit to find the positive and negative inputs for the individual dial.

 

Again, none of the gauges (except the tach signal) have anything to do with the ECU on a 1988.

Tach: receives signal in parallel with ECU, I've installed aftermarket tachs on a couple Renix Jeeps, just use the tach signal wire and you're good to go.

Speedo: On an 88 it's fully mechanical, not sure how you're going to work an aftermarket gauge for this one, either find some gauge that can run mechanical or convert to electrical signal, quite a bit of effort, even more if you have cruise control.

Fuel: I'm not sure if a factory sender will play nicely with an aftermarket gauge, note that the older Renix Jeeps have are Empty=0hms, while the HO's have Full=0ohms. Might need to get your hands dirty and go with an aftermarket tank sender, unless you can get creative with resistors and the like.

Battery: As self explanatory as it gets

Oil: As said above, you might need to get under the hood and tap a new sending unit into the oil filter housing adapter; but the ECU doesn't care about the oil pressure. (no check engine light, etc)

Water Temp: ECU has its own water temperature sending unit in the block, the sending unit in the back of the head only for the gauge. Standard, NPT thread, aftermarket senders thread right in.

For the most part, you can use the existing wiring in the dash, except for possibly the oil pressure gauge depending on the aftermarket system and the speedo, depending on what you choose to do for that route.