Quote Originally Posted by royster View Post
Hello, MI-Mitzu. We live in a frustrating winter.

You'll be able to edit posts once you get a few more posts under your belt.

The best I can offer is to check the wire that goes to the sending unit, and make sure it's not grounding out by way of grease or oil, or shorting out somehow. I was stumped by the pressure relief valve, too, and the book says nothing about it.

Essentially I'm just offering a sympathetic ear, and a shade-tree mechanic's view.
Thanks for that. The pressure relief valve is a bit of a mystery as it is the only suspect item in the FSM for high oil pressure... funny thing is the FSM doesnt really specifiy what high oil pressure is. I'm considering jsut spending the few bukcs ordering a new spring, piston, and washer, but as with any other OEM Mitsu part ordered online it'll take a week and a half to get these and it seems to be a pain to change unless you undo all the belts and remove the harmonic balancer. Sockets are too big as are open and closed end box wrenches.

The assembly diagram for the pressure relief valve is really hard to see, but I assume the piston is going back in correctly.

The truck does have 270k on the odometer and at this age I guess it's not inconceivable the spring could be original and is likely worn.

In the meantime, I'll recehcek the wire for a 3rd time, maybe even cutoff the OE plastic clip and crimp on a new known-to-be-good spade connector and give that a shot as well.

Any other inputs are appreciated.