I have a non turbo rx and it seems that every time i use the 87 octane fuel, i will start to break down on the highway in fifth gear. I will have to downshift into fourth then gain speed to switch back into fifth. But when i put the 89 or 93 in it seems that the problem doesnt occur. I have heard that the 93 is better for the turbo and the lower grades are better for the non turbo. So i guess ill just stick with the 89. Anyone have any ideas why the 87 breaks down?

 

???? 87 is fine for a healthy n/a. Either your timing is off or your fuel system is not delivering enough fuel. Time for a complete tune-up?



Does the car tend to run hot?

 

nah the car runs directly in the middle of the hot and cold.