I have a 2003 Nissan Altima 2.5L 4 cylinder that have antifreeze/coolant leak into the engine oil(when I put coolant in the car it just takes some minutes before everything leaks into the engine oil). I was reading about the possible cause of this on your website which is very informative by the way, but am not sure if my car is equipped with an oil cooler since that is where you guys suggest to start from. If its not equipped with an oil cooler, where would you suggest I start from. Thanks in advance.