I assume the truck has the factory 180 thermostat in it. I bought the truck in december and know it was a one owner. Everything else appears to be stock on the truck, so I doubt he changed the thermostat. I glanced at the water temperature guage when I stopped at the 4.7 mile mark and it appeared to be around the 180 F mark. I didn't look at it climbing up the mountain. The 4.7 mile mark is a stop sign, then I travel another 0.3 mile (approx) to another stop sign at 30 mph. Then through a small town at 35 - 40 mph at a slight incline to the base of the mountain where it turns and is about a 0.8 mile climb to the top. Mountain might be an exageration, but that is what it is officially called here. Also, when I run up the mountain, I am probably at 1/3 to 1/2 throttle, so I am not pushing the truck extremely hard.
Anyways, at this point I believe the thermostat is fully open, the engine block is starting to heat up and radiate heat into the engine compartment at a quicker rate than the outside air flowing though the compartment can remove the heat. With the tube to the fender removed, I think that a lot of the air that was being pulled into the intake was going past the exhaust manifold.
Notice that the air measure at the intake (middle reading) is much slower to change. One reason is the sending unit itself. It transmits a signal only once every 45 seconds approximately. Also, it is about the size of a golf ball. It has two AA batteries in it. Because of its mass, it takes longer to heat up and cool down. So you do have to take that into account when looking at the temperatures. However, you may be right about the filter getting heat soaked, or at least the hot air is trapped under the filter where the other sensor is located. I have checked the temperatures several times now that the truck has been sitting, and the temperature inside the air filter box is staying warmer than the air temp immediatley outside of the air box. Check out the pictures in my gallery and you can see where I have the sending unit attached to the transmission dipstick.
The sending unit in the filter box can change very quickly. You are right, when I stop, it rises quickly. The temp I record is as soon as I come to a stop, but it does rise quickly while waiting to pull out. When getting back up to highway speeds it is starting to drop again.
Quote:
|
................................................. ............65.........Highest temp @ 45mph
|
This is actually the average temp at highway speeds, it climbed while sitting at the stop sign, then came back down and stabilized. It is difficult to write the data down while traveling down the road or to remember what it was when I come to the next stop. Traveling through town, it doesn't cool down as much, reason being less air being pushed through the engine compartment and lower throttle means there is a lower volume of cooler air being pulled into the air filter.