I just wonder which kind of gas I should take for the 04 Solara (4-cyl) will be the most suitable ?
regular? plus? or premium?

Check your owner's manual and the gas filler door for info.

Many cars today will run on 87 octane, but most will benefit from higher octane. Your owner's manual will have the correct info.

I don't have the owner's manual~

87 octane should be fine.

i think 87 should be fine.
you also check on the side of your drivers door and read the tag (where its says the year model, etc) it also says what kind of gas u you need.

Your car will run fine on 87 octane. My 05 V6 uses 87 octane, as recommended in the owner's manual. It also recommends 87 octane for the 2AZ-FE, which is the 4-cylinder engine. In my experience, and most auto experts agree, using premium gasoline would be a waste of money. The slight increase in power you might get with the 4 cylinder engine is not worth the additonal cost. Good luck and enjoy your new car. Hy

That would be regular unleaded. It is a waste of money to put higher octane in (like a 91 or higher octane). The octane amounts are on the pumps and are usually labeled as mid-grade or silver.
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