My 2007 RX350 seems to run the same on mid-grade as it does on premium. Am I hurting the engine by not using premium all the time? Other Toyota products with this 3.5 engine and 270 horsepower only require regular gas. Help??

 

your ecu/engine realizes that you have poured lower octane gas in the car and it will retard the timing and basically dumb down the car by 10 15%. Are you leasing the car or have you purchased it?

The only thing that might happen, as it did to me is the knock sensors might go bad after a while. When we bought our LS400 the previous owner never told his wife she had to put premium gas in so the car seldom had 91 in it. So when we purchased it and began using 91 octane the check engine light came on, my mechanic said it was a knock sensor. Long story short we had to replace the knock sensors (one in each bank of cylinders V8) and the car now runs perfectly without any problems .


There has been tons of discussions regarding this subject both on CL and various other sites on the net. Id say search a bit more and see what you come up with.

 

Mid grade is good enough, trust me.

 

Ditto! I put in 87 and it works!

 

Only time we use premium is when we are going to do a lot of mountain driving and want all the horsepower that the V6 can produce. Otherwise we tend to run midgrade or regular. Only noticable difference is slightly lower mileage and a bit less get-up-and-go.

 

not this again. i wonder how long before someone jumps in and says that youre a crazy fool for even considering putting anything less then 93 octane in your car. i still use 87 and the cheapest 87 i can get, car runs ok, well as ok as the RX can get.