Hi everyone I have a 96 mazda b2300 it is the same as a ranger so I am here. My truck will not get warmed up and always stays in open loop. I was able to warm it up by putting a piece of cardboard in front of the radiator and it finally went into closed loop. I just changed the thermostat and temp gauge I believe the thermostat is a 192. The truck kept throwing me a 1st cylinder miss code(p0301) so I cleared it and did the cardboard trick and it hasn't popped back up. Has anyone had this happen before???

 

Welcome to the forum

2.3l Lima engines do not generate alot of heat, radiator is hardly used at all in winter when temps are below 45degF.

The cardboard in front of rad is to lower air flow in the engine bay, the engine metal itself cools engine too fast when temps are low, lol.

They do make a 205degF thermostat for these.
Some even remove the fan in the winter, really not needed, but as long as the fan clutch is working it would never lock because radiator would never warm up