1990 Geo Prizm MPG & Specs — Real-World vs EPA, All Trims
Every trim takes regular — no premium needed.
Is the 1990 Geo Prizm good on gas?
At up to 27 MPG combined, the 1990 Geo Prizm is better than average for a Subcompact Cars — that class averages about 22.8 MPG across 5,756 EPA-tested versions, so it's a good pick on fuel for its size.
Real-world MPG vs the EPA number
The EPA figures above come from a standardized dynamometer test, not the open road — real-world MPG typically runs a bit lower depending on your driving, climate and terrain. That's true of every car on this site, old or new.
This 1990 model was originally EPA-tested under the pre-2008 2-cycle method, which didn't account for highway speeds over 60 mph, air-conditioner use, or cold starts. When EPA overhauled the test for model year 2008, city ratings fell by about 12% and highway by about 8% on average industry-wide — and EPA retroactively adjusted every 1984-2007 rating to the stricter standard so old and new cars could be compared fairly. The MPG above is already on that modern scale — the window sticker on this car when it was new likely showed a higher, pre-2008-method number.
At today's AAA national average price — $3.80/gal for regular gas as of 2026-07-05 — the most efficient trim runs about $2,111/year (roughly $176/month, about $14.07 per 100 miles) at the EPA's assumed 15,000 miles/year, using an estimated 556 gallons a year. We don't estimate a cost-per-fill since exact tank size isn't in the public EPA dataset, but the per-100-mile figure scales to any tank. Current national average gas prices →
1990 Geo Prizm trims & fuel economy
| Trim (engine / transmission) | Fuel | MPG | Fuel/yr (today's price) |
|---|---|---|---|
| 1.6L 4-cyl, 5-spd manual, FWD | REGULAR | 27 | $2,111 |
| 1.6L 4-cyl, 5-spd manual, FWD | REGULAR | 25 | $2,280 |
| 1.6L 4-cyl, Automatic 3-spd, FWD | REGULAR | 24 | $2,375 |
| 1.6L 4-cyl, Automatic 4-spd, FWD | REGULAR | 23 | $2,478 |
1990 Geo Prizm specs
What the EPA test-car listings record for this model year — every combination sold is a row in the trims table above.
| Engine options | 1.6L 4-cyl |
| Transmission | 5-spd manual · Automatic 3-spd · Automatic 4-spd |
| Drive type | FWD |
| EPA body class | Subcompact Cars |
| Fuel | Regular |
Other years of the Geo Prizm
Similar cars (Subcompact Cars)
Cars that take premium · Cheapest cars to fuel · Where fuel grade depends on the trim · Fuel guides
4 trim(s) · EPA FuelEconomy.gov data retrieved 2026-07-24 · fuel prices AAA national average as of 2026-07-05.