Hey guys, I have a 1994 Pickup 22re, that doesn’t want to get to operating temperature, I know it can’t be the sensor because after driving a while, the lower radiator hose is not hot, I can hold on to it. The thermostat is 190F and works fine, the fan clutch seems to be fine, it doesn’t engage because the truck doesn’t get up to temp, I know it works because I can here it roar on a cold start then come back down, this one has me stumped. I don’t know where to go from here, if anyone could give me a couple points that would be greatly appreciated. Thanks
- Cesar

The gage doesn’t rise any higher than this!

 

That's where mine is when at normal operating temp. Only goes higher, to about halfway point, when ascending Cajon Pass, Tehon Pass or Hwy 190 in Death Valley in warm weather.

 

If you've tested the thermostat and it indeed is not opening until 190 degrees, it's pretty hard to believe the engine isn't coming up to temperature. With a closed thermostat, the engine will warm up.

The lower radiator hose is the outlet of the radiator, so one wouldn't expect it to be all that hot.

I would suspect a sensor/gauge problem. Get an IR thermometer and measure the temperature of the top hose at the outlet of the thermostat when the engine is "warm".

Also, does your heater put out significant heat? That's a good test of whether or not the engine is warming up properly.

 

This fit my factory '92 radiator, good way to confirm stock gauge/sending unit & t-stat are working correctly. Seems very accurate:



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Where did you get that cap? Looks pretty useful.

 

Yes, That's Nice Paul!

 

link: