Isuzu I-Mark
What it costs to keep fuelled
$1,690a year, fuel only
The 1989 Isuzu I-Mark is EPA-rated at 28.4 MPG combined (25.8 city / 32.4 highway). Over 15,000 miles a year that is about 528 gallons, $1690 a year in fuel, or $0.113 per mile at $3.20/gal.
Across its full 1984–1989 run it averages 28.1 MPG, improving by 1.6 MPG over 6 model years.
The band is how far one gallon carries it: 28.4 of the 60 MPG this scale runs to. The square tick is the subcompact cars average, 24.1.
- Fuel, per year
- $1,690 at 15,000 mi
- Per mile
- $0.113
- Per kilometre
- $0.070
- Gallons burned/yr
- 528
1 mile = 1.609344 km · fuel at $3.20/gal, fixed JUL 2026
Test figure — not a road resultSOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
How this is worked out
- Start from the EPA combined figure for the model year — a laboratory test cycle run to a fixed procedure, not a road result. Where a year sold several engines or drivetrains, the trims are averaged and the trim count is printed beside the row so you can see how much averaging is behind it.
- Fix a pump price. This site keeps one reference price, $3.20 a US gallon, fixed JUL 2026 and printed next to every dollar figure it produces. It is an assumption with a date on it, not a quote — put your own price in.
- Fix an annual distance. Every annual figure on this site uses 15,000 miles a year, roughly the US average. A cost per year with no stated distance is not a number, it is a mood.
- Divide distance by economy for gallons, multiply by price for the year's fuel, divide price by economy for one mile. The per-kilometre line is that last figure divided by 1.609344 — the same money, in the unit most of the world drives in.
- Stop there. No depreciation, no tyres, no insurance, no servicing. This is the fuel line of the ledger and it is labelled as one; depreciation usually dwarfs everything on it.
gallons/yr = miles/yr ÷ MPG fuel $/yr = gallons/yr × $/gal cost $/mi = $/gal ÷ MPG cost $/km = cost $/mi ÷ 1.609344
The full method, the licence note, and what a test figure cannot tell you →
Re-run the ledger at another pump price
Every line above rests on one pump price. Here is the same entry re-costed at six others, because the price is the part that changes while the test sheet stays put.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.088 | $880 | $1320 | $1761 |
| $3.00/gal | $0.106 | $1056 | $1585 | $2113 |
| $3.20/gal | $0.113 | $1127 | $1690 | $2254 |
| $3.50/gal | $0.123 | $1232 | $1849 | $2465 |
| $4.00/gal | $0.141 | $1408 | $2113 | $2817 |
| $4.50/gal | $0.158 | $1585 | $2377 | $3169 |
| $5.00/gal | $0.176 | $1761 | $2641 | $3521 |
SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
The whole service history, sheet by sheet
6 model years on file. Read down the combined column: a nameplate that got heavier shows it here long before any brochure admits it.
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 1989 | 28.4 MPG | 25.8 | 32.4 | $2220 | 317 | 5 |
| 1988 | 29.8 MPG | 27.3 | 33.8 | $2100 | 301 | 4 |
| 1987 | 29.8 MPG | 27.3 | 33.8 | $2100 | 301 | 4 |
| 1986 | 31.7 MPG | 29.3 | 35 | $1983 | 282 | 3 |
| 1985 | 22 MPG | 20.5 | 24.3 | $2838 | 405 | 4 |
| 1984 | 26.8 MPG | 25.2 | 29 | $2700 | 367 | 9 |
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.
SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
Marked against the rest of the subcompact cars bay
Among the 229 subcompact cars models tracked here, the Isuzu I-Mark ranks 41 on current figures, against a class average of 24.1 MPG — the square tick on the gauge above.
Closest more-efficient alternatives in the same class: Chevrolet Aveo 5 (28.5), Audi A3 Cabriolet (29), BMW M440i Convertible (29), BMW M440i xDrive Coupe (29), Lexus LC 500h (29).
Tailpipe CO₂ is rated at 317 grams per mile, which works out to roughly 4.8 tonnes a year at 15,000 miles.
Questions asked across the counter
What MPG does the Isuzu I-Mark get?
The 1989 Isuzu I-Mark is rated at 28.4 MPG combined by the EPA — 25.8 city and 32.4 highway. Across all 6 model years in the database it averages 28.1 MPG, ranging from 20 to 35 depending on year and trim.
How much does a Isuzu I-Mark cost in fuel per year?
At 28.4 MPG and 15,000 miles a year, it burns about 528 gallons — roughly $1690 a year with fuel at $3.20 a gallon, or $0.113 per mile. The EPA's own published annual figure for the 1989 model is $2220.
Has the Isuzu I-Mark become more efficient over time?
Yes. It has gone from 26.8 MPG in 1984 to 28.4 in 1989 — an improvement of 1.6 MPG, or 6% across 6 model years.
Is the Isuzu I-Mark efficient for its class?
It ranks 41 of 229 in the Subcompact Cars class on current figures, against a class average of 24.1 MPG. That is 4.3 better than typical for the class.
Pull another logbook off the same shelf
Same class, nearest economy first — the ones a buyer is genuinely choosing between.
SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
Cost per mile, per kilometre and per year are computed at a reference price of $3.20 a gallon over 15,000 miles, fixed JUL 2026 — set your own pump price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.
