[2JZGTE]

In my car the temp. can jump around a little depending on outside temp, traffic, humidity etc. Cruising on freeway temps range from 70 to 80c depending on conditions. When its a little cooler ouside, sometimes my car doesn't even want to heat up to the 90c that I have it set to when sitting in heavy traffic. When it's warmer it always goes up to the 88-90c operating range. FYI my car has koyo radiator with twin FAL fans and Pivot fan controller.

Again, always check your coolant level. If it's been a long time change it and add bottle of water wetter, the stuff always makes my cars happy. Neglected coolant always gets the best of my friends' cars.

As far as the exhaust leak, after everything heats up...the exhaust leaks will actually seal off better. You will hear the exhaust leak the most when you first start the car and everything is cold. As your engine/exhaust heats, the metal expands and bad gaskets seal up a little. Doubt an exhaust leak would make your engine run hotter though.

Check your coolant...maybe change it. From what I've read I think your car's acting normal. Sometimes mine also runs down at 70degrees, and sometimes it goes up to normal 80-90c. Cars with Koyo radiator/twin fans etc. tend to sometimes run so cold they don't even get up to optimum temps. I don't like to run too hard if it's below 70degrees for fear that piston rings haven't completely expanded, but it's probably not that bad. I just always wait until it's nice and hot before stomping it.

Let us know if you do find a problem...but ya, probably just your Koyo running cold. They work really well.