Alphadog1

I was measuring my oil temperature this morning and my oil temp spiked to 320 F after 30 minutes of stop and go city traffic and then settled to about 220 F . Ambient air was at 48 F and Engine temp was between 180 and 190 F

Alphadog1

This afternoon the Oil temp never got above 210F with ambient 48 F.

-Wes-

Curious. How long was it registering as elevated like that? Even brief periods of over-heating at that level can destroy the protective qualities of your oil. However, if it did get that hot, you should be able to check the dipstick and see that it looks extremely dark/black, even if you just changed it recently.

drjonez

That isn't good. A good synthetic will tolerate 300F, but much more than that and it starts breaking down.

Not much help here for comparison as I have a TDI. I've see high 200s towing in high ambient heat.

Alphadog1

It was about 5 minutes. I wonder if it is the sensor since I was getting an intermittent Oil Level Thermal Sensor failure previously, but not at the time of the temp spike. I have about 3000 miles on the oil. I will check the oil in the morning for discoloration or burnt appearance. It was about 5 minutes. Does anyone know how the oil cooler works ? Is it continuous flow or is it thermostatically controlled?

J. Patterson

Just instinct based on experience. I suspect the sensor. It would be almost impossible for oil temp to be 350°F while coolant temp was normal at 220°F. If it WERE that hot, there would be visible smoke if you removed the oil filler cap.

Alphadog1

It was 320 F, most likely the sensor. I will change the sensor.

Alphadog1

Got a dashboard oil level sensor defective warning while driving this AM. I turned on the OBD11 app on my phone and the oil temperature was reading 380 F. When the dash board warning went away the temperature was 199 F. Bad sensor

Corrado Alley

WOW, I've seen 320F on my 3.6 Corrado but that was on a VERY spirited run on the tail of the dragon running 5,000-7,000 rpms chasing a buddy before I did additional cooling mods. I run Amsoil and did an oil analysis afterwards and the report was fine.

I find it somewhat hard to believe that the oil temps on a stock q7 were that high however the plastic belly pan and hood being so tight don't allow the heat to escape and low speeds cause heatsoak. I've seen these same problems on my corrado. I had to pull my skid plate to allow air/heat escape and have even added hood vents. To this day in stop and go traffic with the ac on I can see the temps climb, I need to increase my radiator size.

You might want to have the cooling system pressure checked. You might be due for a new coolant reservoir cap or have a minor leak in the radiator. While the 3.6 is pretty robust on its cooling system and more notably the crack pipe and thermostat housing it is fairly old on yours. Uro sells an aluminum one that after a little clean up is pretty good.

Alphadog1

I think it was a bad sensor. I will change the sensor and see what readings I get. My engine belly pans are are not installed but you still get a lot of heat in the engine compartment. Hood vents would definitely help on the Q7. Which pipe should be Aluminum? The thermostat housing?