I just recently purchased a 2004 g35x sedan from my uncle.

He got it in 2006. Ever since he has owned, he has always used regular gas in it. This is because the manual states that the car RECOMMENDS 91 octane but does not require it.

My concern is that i definitely feel that the car runs a bit sluggish because of such prolonged use of regular gas.

I want to start permanently using 91 + octane, but my question is should i reset the ecu?

And if so, are there any disadvantages or precautions i need to worry about?

Thanks!

 

Omg..haha good for you on going to 91 (its literally like $3 extra per fill up if you had a bone dry tank)

You don't need to do a reset, but it wouldn't hurt. The computer learns your driving style, so if your dad drove like your grandpa, its gonna act like that. Just disconnect the negative battery cable for 10 minutes and it'll reset it. It takes about 200 miles to work out its learning process tho.

 

Thanks for your quick response buddy.

I also heard there's another easier way for the ecu to reset without removing the battery? Do you know if it also works just as good?

And also, if I was to start using 91 octane in the car and decided to drive a lot faster and rougher, would the ecu be able to adapt without the reset or do you think it would take too long?

I want to reset the ECU but i just hope that it doesn't ruin anything in the car.

 

There is a pedal procedure, but I don't know how it can get any easier than just disconnecting the battery.

It won't ruin anything at all. You disconnect the battery every single time you install a new part on the motor.

It would adapt without it, but like you said, it would take forever.

 

Thanks so much ScraggleRock, I will reset my ecu after i fill up with premium gas.