Alright this aint my section but my girlfriends brother is looking at this XJ, its an 88, 160xxxmiles, 4.0, 5 speed (man), 4x4. Now it drives great shifts perfectly but the only problems are the temp gage doesn't work, it seems like it stuck at 110 cold or hot, and the oil press. doesn't work. Think its just some sensors or sending units? This year have electrical problems? Any advice will help alot.
TIA from a ZJ guy.

 

Any year can have electrical problems. In this case I would say it's just the age, they go bad probably just the sending units sometimes the connections at the back of the guages get corroded up. I would not stress but I would get the units asap so you don't get burned. Pretty good mileage for the year BTW.

 

Yeah the mileage is good, my 98 ZJ has 237xxx and counting.
I heard over on JeepForum (My native place) that the trans that comes with the 88 the so called "pukegoat" is a POS. Wondering if you had any opinions on it? And the Renix engine, any good?

 

The peugot is garbage.

 

The Peugot tranny is weak, the Renix motor itself is fine. It's just down on power a bit from the HO motor, big difference is the fuel injection system. There are a lot of people on this forum rocking the Renix motors without any difficulty.

I'd say try replacing a sending unit and see if that does it. The coolant sending unit is like $15, not a huge deal if it doesn't fix the issue. Not sure what the oil pressure sending unit costs, but I can't imagine it's more than $30.

 

Replace the sensing units - the oil pressure sensor is down by the base of the distributor, and the temperature gage sensor is at the driver's side rear of the cylinder head. Both are common parts (if you don't mind waiting a bit, you can get them from Morrix 4x4 Centre for a good price.)

You say the transmission "shifts fine" - gearbox or slushbox? The automatic used was the Aisin-Warner AW4, and is a very solid slushbox (I put it somewhere between the later THM700R4 and the THM350 in terms of duty rating and durability. I've put some through an incredible amount of abuse - just keep it cool and keep the fluid changed!)

For the 88, the five-speed behind the six cylinder was the Peugeot BA-10/5, which was designed for about 2/3 the weight, half the engine, and mebbe half the torque (it's the old Peugeot 505 gearbox with a different bellhousing.) The 1989-1993 AX-15 is a direct replacement, the 1994-1999 AX-15 will require a different pilot bushing and a hydraulic swap. The 1999-up NV3550 in TJ and XJ can also be used, but the swap is a bit more involved. Grab the transfer case from the donor as well, since the spline count changed.

If you've got the AW4, just keep the fluid changed and have no fear.

The RENIX control system is a pre-OBD setup built by Bendix/King Avionics, and most troubleshooting can be done with a common DMM. The manual on the system is available online (I keep a copy at my RENIXPower group - groups.yahoo.com/group/RENIXPower. Make sure you let me know why you're there...)

I have had five RENIX XJ's to date (1987, 1988, 1989, 1989, 1990) and still have the 88 pending refit. I vastly prefer the RENIX engine to the OBD-I, and the OBD-II setup is merely a close second (I came up on points & condensers, and I prefer to do my own thinking. RENIX doesn't "store" or "throw" codes, the CEL/MIL is merely a holdover from the GM 2.8L V6, 1984-1986.)