FuelFacts

Does the 1984 Isuzu I-Mark need premium gas?

Fuel grade varies by trim — see the breakdown below.

Trim (engine / transmission)FuelMPGFuel/yr
1.8L 4-cyl, 5-spd manualREGULAR23$2,700
1.8L 4-cyl, 5-spd manualREGULAR23$2,700
1.8L 4-cyl, Automatic 3-spdREGULAR22$2,850
1.8L 4-cyl, Automatic 3-spdREGULAR20$3,100
1.8L 4-cyl, 4-spd manualDIESEL35$2,250
1.8L 4-cyl, 5-spd manualDIESEL32$2,450
1.8L 4-cyl, 5-spd manualDIESEL32$2,450
1.8L 4-cyl, Automatic 3-spdDIESEL27$2,900
1.8L 4-cyl, Automatic 3-spdDIESEL27$2,900
The EPA records the fuel each version was tested on. Whether premium is strictly required or just recommended is an owner's-manual detail the EPA dataset doesn't include — so we don't guess it.

9 trim(s) · EPA FuelEconomy.gov · retrieved 2026-06-14.