Engine Operating Temp

I have a scan guage on my truck and like to keep an eye on the engine operating temp. For most of the time I have owned the truck it has sat at 181-182 degrees with little fluctuation. Hot, cold outside, engine under load going up hills, it has held more or less steady.

Last winter the temp started fluctuating though. It would sit from 175 to 197 depending on how I was driving. With 100k on the truck, I figured it was time to flush the coolant. Figured I should do the water pump and t stat while I had the coolant out since the water pumps on these trucks tend to go and the t stat is cheap and possibly my problem.

Anyway, I did all this last weekend. Everything went back on fine. I got an OEM t stat and water pump. Refilled the coolant. Drove some, checked the level, added some until it was full. The temperature still changes some driving. It's been from about 181 to 190 now. It doesn't stay over 182 for long, and comes back down after I take the load off the engine. It just never went up that high before.

My question is is this normal and what do other people with scan/ultra gauges usually show for temps? Also, wondering if it is the temp sensor or something else that could be causing my problem?

 

After having a shop do my t-belt change along with thermostat and water pump my temps on my ultra guage were in the 203-210 range and it would fluctuate a lot. After researching and checking the work of the shop who installed the thermostat I realized they installed the t-stat with the jiggle valve up in the 12:00 position. So I rotated the thermostat so the jiggle valve is now in the 6:00 position and my temps have drastically changed. I'm now n the range of 188*- 192*. Which for me is about 20* cooler and much more stable at 190.

So check the jiggle valve. I didn't think it would effect the temps but after reading so many stories of other guys doing this and the. Seeing the difference it made on my truck, believe me it does make a difference. Plus for the 3.4l the manual states for the jiggle valve to be in the 6:00 position. Hope this helps


EDIT: oops, forgot to check what year truck you have. Check the manual for the 4.0 and see what it says about the thermostat position for your engine.

 

My 2013 TRD 4.0L has sat at 188-192 when in operation and fully warmed up since the day I took it from the dealership. When I browse around here it seems like that's the normal operating temperatures for the 2nd gen V6 Tacoma. If my truck regularly ran at 172, I'd be worried that it was never warming up enough to achieve optimal combustion and operating temps.

When I tow 5000 lbs the temps will sometimes hit 200-202 when going up a sustained long grade with the supercharger whining, but it's never concerned me since that's still a long way off from a damaging temperature.

 

going to echo this as well... my truck behaves the same.

 

184 to 192

 

186-190

 

Depending on the ambient temp and the load on the engine - 185 - 197. Usually 188-193

 

Summer I'm running 188-192. That's louisiana heat, city driving at 94 degrees ambient

Winter I was seeing 180-186.

 

I have a URD TCAI. Intake temp will never go above ambient temperate when driving, but it'll scream up at idle and drop real quick once I get going

 

we aint talking bout air intake temps... we are talking about coolant temps.

FYI stock intake exhibits the same thing... literally 1-2*F above ambient max at cruising speed, but stopped temps go up for obvious reasons.

 

that's right where my old 3.4 L used to run


Thanks for the input guys. Guess i am just being OCD about it and it's normal...

 

my truck runs about 186.8 95% of the time. Going up steep hills or towing, it sometimes creeps up to 195ish, which i was worried about, but it seems that is normal.

 

Thread revival.

I don't normally check the temp, but noticed it was running between 190 and 194 on the highway yesterday. I thought the thermostat was a 180, so wondered if I was running a little hot. Looks like that is a normal range.

FWIW, I have a 2011 4.0L w/ tow package. Currently around 165k miles on the original coolant. Changing the coolant is on my list.