Yesterday I was examining the Lexus NX200t, which has a 2 Liter turbocharged engine good for 240 HP. I was astonished that it used a water-to-air intercooler. First time I see a factory Turbo with water-to-air!
Notice two coolant reservoirs, one for the engine radiator and the other for the intercooler.
The intercooler water pump:
My guess is Toyota is looking for a compact design. I'm not sure if there is a radiator dedicated for the intercooler or is it using the engine radiator, but since there is a separate reservoir for it I'm guessing it does. I couldn't see clearly, with all the covers around the grill area hindering visiblity.
Another interesting observation is the placement of the MAF sensor. Usually the MAF sensor would be on the charge pipe, cool side (if it is air-to-air), but in this case it is pre-turbo, right next to the air filter. My guess is because of the water-to-air, there is no cool side of the charge pipe. So putting it in the charge air pipe, which will be hot, will throw off the reading. So they put it pre-Turbo.
Notice two coolant reservoirs, one for the engine radiator and the other for the intercooler.
The intercooler water pump:
My guess is Toyota is looking for a compact design. I'm not sure if there is a radiator dedicated for the intercooler or is it using the engine radiator, but since there is a separate reservoir for it I'm guessing it does. I couldn't see clearly, with all the covers around the grill area hindering visiblity.
Another interesting observation is the placement of the MAF sensor. Usually the MAF sensor would be on the charge pipe, cool side (if it is air-to-air), but in this case it is pre-turbo, right next to the air filter. My guess is because of the water-to-air, there is no cool side of the charge pipe. So putting it in the charge air pipe, which will be hot, will throw off the reading. So they put it pre-Turbo.