Has anybody installed an oil temperature gauge on a 1HDT? If so, where did you install the sensor and what temps are you getting? I installed the temp sensor on the factory oil pressure sender location using a tee. After a 30 minute drive, oil temp peaked at only 68 degrees Celcius. Seems low to me, unless the factory oil pressure sender port gets cooler oil from the oil cooler?
1HDT oil temperature
- Thread starter HRTROB
- Start date
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Considering your coolant temp is around 80c, it cant be too far off. Maybe coolant is warmer because it is wrapped around the bores and passes through the head hot spots
- Thread starter
- #3
In my other vehicle, the oil temp was higher than the coolant temp until I installed an oil cooler. Now the oil temp in that car is the same or just a bit lower than the coolant temp. I thought it would be the same case with the 1HDT, especially with oil passing thru a hot turbo.
That outlet in the block was designed for pressure, not oil temp, so the oil in there is most likely not being circulated.
- Thread starter
- #5
Okay I think I know why the oil temperature is reading low. It's the tee.
A couple of years ago I installed an oil temperature gauge on my other car (Toyota 86) with the sensor installed on the factory pressure switch location for the oil pressure idiot light. The gauge would read exactly the same as what is displayed on my scangauge from the OBD port since the factory oil temp sender is beside where I installed the aftermarket sender. Recently I decided to make the idiot light functional again by using the same tee I used on the 1HDT. The result is that the aftermarket gauge now has a huge delay like in the 80 and it reads 15-20 degrees Celcius lower than what's displayed on the scangauge. Attached is the tee I used. Temp sensors installed inline to the threads since they're too long for the port on the side.
Tee with aftermarket sender and pressure switch on the left, and the factory oil temp sender right beside it.
A couple of years ago I installed an oil temperature gauge on my other car (Toyota 86) with the sensor installed on the factory pressure switch location for the oil pressure idiot light. The gauge would read exactly the same as what is displayed on my scangauge from the OBD port since the factory oil temp sender is beside where I installed the aftermarket sender. Recently I decided to make the idiot light functional again by using the same tee I used on the 1HDT. The result is that the aftermarket gauge now has a huge delay like in the 80 and it reads 15-20 degrees Celcius lower than what's displayed on the scangauge. Attached is the tee I used. Temp sensors installed inline to the threads since they're too long for the port on the side.
Tee with aftermarket sender and pressure switch on the left, and the factory oil temp sender right beside it.
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Where did you get the water temp from? I’m about to install a water temp/ oil pressure gauge. I ordered a T similar to yours along with a new OEM sender.
- Thread starter
- #7
Sorry for the late reply, just saw this now. For the coolant temp I used a hose adapter (forgot the diameter) and installed it on the upper radiator hose.
