I just got my XJ and it came with an Oil pressure gauge stuck on 80. I picked up a new sender and now I get lower readings (sometimes too low)

After fixing (kinda) the oil pressure gauge I am having erratic readings from my temp gauge. It will suddenly go to 240 or higher and the check gauges light comes on. It has never overheated though. If I give it about 30 seconds it will always return to normal and the light will go out. Any ideas on this one?

I'm going to a mechanical oil pressure gauge to see if that will fix my low reading issue.

 

You can try and replace the coolant temp sensor on the thermostat housing, and see if that works.

 

I suggest doing this as well and it's also a good idea to manually check your coolant temperature with a cooking thermometer just to make sure your are not overheating. I would also pull the thermostat out and drop it boiling water to make sure it is working properly.

 

Pretty sure the coolant temperature switch on the thermostat housing is for the electric fan. The temp sensor for the guage is located on the back end of the head.

 

I'll have to get the Haynes Manual out and check now...

 

depends on the year. older ones have a separate Gauge sending unit. the newer ones just have the ETC sensor on the t/stat housing and sends it to the Gauge and the ecu.

but the 2000 just has the ect sensor On the t/stat housing.

 

I'll buy that. My renix jeep has three...

 

You Renix owners..... lol