Pontiac Sunbird Convertible
21.8 MPG The 1991 Pontiac Sunbird Convertible is EPA-rated at 21.8 MPG combined (18.8 city / 27.3 highway). Over 15,000 miles a year that is about 688 gallons, $2202 a year in fuel, or $0.147 per mile at $3.20/gal.
Across its full 1985–1991 run it averages 22.4 MPG, essentially flat across 7 model years.
Running cost at different fuel prices and mileages
The figure everyone actually wants, and the one the EPA does not publish — because it depends on a fuel price no agency will commit to.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.115 | $1147 | $1720 | $2294 |
| $3.00/gal | $0.138 | $1376 | $2064 | $2752 |
| $3.20/gal | $0.147 | $1468 | $2202 | $2936 |
| $3.50/gal | $0.161 | $1606 | $2408 | $3211 |
| $4.00/gal | $0.183 | $1835 | $2752 | $3670 |
| $4.50/gal | $0.206 | $2064 | $3096 | $4128 |
| $5.00/gal | $0.229 | $2294 | $3440 | $4587 |
Every model year
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 1991 | 21.8 MPG | 18.8 | 27.3 | $2875 | 411 | 4 |
| 1990 | 22.3 MPG | 19 | 27.5 | $3150 | 400 | 4 |
| 1989 | 22.3 MPG | 19 | 27.5 | $3150 | 400 | 4 |
| 1988 | 22.5 MPG | 19.8 | 28 | $3150 | 398 | 4 |
| 1987 | 23 MPG | 20 | 28 | $3088 | 390 | 4 |
| 1986 | 22.8 MPG | 20.3 | 27.3 | $3125 | 395 | 4 |
| 1985 | 21.8 MPG | 19.5 | 26 | $3358 | 411 | 6 |
Where a model year offered several engines or drivetrains, the figure is the average across all EPA-tested trims that year — the trim count is shown so you can see how much averaging is involved.
How it compares in its class
Among the 229 subcompact cars models tracked here, the Pontiac Sunbird Convertible ranks 133 on current figures, against a class average of 24.2 MPG.
Closest more-efficient alternatives in the same class: Audi S5 (22), Audi S5 Cabriolet (22), BMW 328ci (22), BMW 335ci (22), BMW 335ci Convertible (22).
Tailpipe CO₂ is rated at 411 grams per mile, which works out to roughly 6.2 tonnes a year at 15,000 miles.
Questions
What MPG does the Pontiac Sunbird Convertible get?
The 1991 Pontiac Sunbird Convertible is rated at 21.8 MPG combined by the EPA — 18.8 city and 27.3 highway. Across all 7 model years in the database it averages 22.4 MPG, ranging from 19 to 26 depending on year and trim.
How much does a Pontiac Sunbird Convertible cost in fuel per year?
At 21.8 MPG and 15,000 miles a year, it burns about 688 gallons — roughly $2202 a year with fuel at $3.20 a gallon, or $0.147 per mile. The EPA's own published annual figure for the 1991 model is $2875.
Has the Pontiac Sunbird Convertible become more efficient over time?
Barely. It sits at 21.8 MPG today against 21.8 in 1985 — essentially flat across 7 model years, with efficiency gains offset by weight and power creep.
Is the Pontiac Sunbird Convertible efficient for its class?
It ranks 133 of 229 in the Subcompact Cars class on current figures, against a class average of 24.2 MPG. That is 2.4 worse than typical for the class.
EPA test figures from fueleconomy.gov. Cost per mile and annual fuel spend are computed at a reference price of $3.20 per gallon — use your own price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.