I just wanted to post this for the cheap guys like me.

"I researched and found out not using premium gas could pop up the check engine light, I only used mid grade two times and the engine light came on. When I got home I filled up with premium and fuel management filler. I reset my battery and have been running the car for about 20 miles now with no check engine light on. I guess honda's are picky about their octane."

For $1.20 more a fillup I guess it would be worth using premium...

 

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I think you need to be more specific. All the non-USDM engines pretty much require premium. And I think they all (usdm, jdm etc) say you should use it, but its not necessarily needed. Once you jump into a vtec motor, or start adding bolts-ons, I would def. use it.

Whats the octane in jdm land....98? lol

 

I heard in Japan they use crazy octane for a norm. Mine is a 98 Prelude S USDM. It says to use premium but I went with mid grade twice. That through off a check engine light. I went back to premium and reset the computer. Now it stays off, hopefully for good.

 

VTEC - premium.
Non-VTEC - wutever
Non-USDM - premium

 

i'm almost 101% sure that putting midgrade in ur fuel tank instead of premium won't give u a cel, and that the CEL is probly for something else, so if and when it come back on I would get it checked.

 

the CEL could be anything from you not tightening your gas cap, a bad gas cap seal, or even the fact that the computer is changing timing based on the fuel mixture.... whats the code? im willing to bet it's an EGR code, and you just need to fix the gas cap...

 

I forgot the code, I thought it was because of the fuel because I saw on the site "forgot where" that not using premium could set off the light. I have the code at home il post it.

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