1990 Mercedes-Benz 420SE: MPG and fuel economy
The 1990 Mercedes-Benz 420SE is rated by the U.S. Environmental Protection Agency at 13 combined MPG, with 12 MPG in the city and 15 MPG on the highway. That lands well below the average for cars in the Midsize Cars class in the same model year.
This page collects every fuel-economy figure the EPA publishes for the 1990 Mercedes-Benz 420SE. Below you will find the headline combined, city, and highway MPG, the estimated annual fuel cost at three different driving levels, the tailpipe CO₂ emissions, and a full breakdown of the engine and drivetrain.
Key takeaways
- Returns 29% worse combined MPG than the average car in the Midsize Cars class for the 1990 model year (18.3 MPG class average).
- The most efficient car in the Midsize Cars class for the 1990 model year is the Chevrolet Corsica at 24 MPG.
- EPA estimates this car costs around $15,750 more in fuel over five years than an average new vehicle of the same model year.
- Subject to the federal Gas Guzzler Tax, which applies to passenger cars rated below 22.5 combined MPG.
- Requires premium gasoline, which typically adds about 40 to 60 cents per gallon to the EPA's annual fuel cost estimate.
Fuel economy at a glance
These are the EPA's official ratings for the 1990 Mercedes-Benz 420SE. The numbers come from a standardised laboratory test cycle and are the same figures that appear on the window sticker of every new car. Real-world mileage varies with driving style, weather, fuel quality, and how heavily loaded the car is.
Combined MPG is a 55/45 weighted blend of the city and highway test cycles. The EPA uses it as the single number you can compare across the entire dataset, including hybrids and EVs (which use the equivalent MPGe figure).
| Combined MPG | 13 MPG |
| City MPG | 12 MPG |
| Highway MPG | 15 MPG |
| Annual fuel cost | $5,300 |
| Tailpipe CO₂ | 684 g/mi |
| Fuel type | Premium |
How the 1990 Mercedes-Benz 420SE compares
The 1990 Mercedes-Benz 420SE returns 13 combined MPG. Cars in the Midsize Cars class for the same model year average 18.3 MPG, which puts this car behind the class average by about 29%.
The most efficient car in the Midsize Cars class for the 1990 model year is the Chevrolet Corsica at 24 MPG. The bar chart below puts the Mercedes-Benz 420SE alongside the class best and the class average so you can see the full picture.
For broader context, the average new car of the 1990 model year (across all classes) returns 19.1 MPG. Larger vehicles pull the all-cars average down, so do not use that figure on its own to judge a small car or a hybrid. The full list of the most efficient cars of the 1990 model year is on its own page.
Annual fuel cost across driving patterns
The headline annual fuel cost the EPA publishes assumes 15,000 miles of driving per year and a fuel mix of 55% city and 45% highway. The dollar figure is calculated using the EPA's current reference price for premium gasoline, which is $4.61/gallon. EPA updates that reference periodically rather than tracking live pump prices, so treat it as a window-sticker estimate rather than today's pump number.
The table below scales the EPA's number to three common driving patterns. The combined MPG and the reference fuel price stay constant, only the annual mileage changes. To get a current-prices estimate, take your local gas price and multiply by 1153.8 gallons (the car's annual consumption at the rated MPG).
| Driving pattern | Estimated annual fuel cost |
|---|---|
| Light driver, 7,500 miles per year | $2,650 |
| Average driver, 15,000 miles per year | $5,300 |
| Heavy driver, 25,000 miles per year | $8,833 |
Compare against other Midsize Cars for 1990
If you are cross-shopping the 1990 Mercedes-Benz 420SE, the most useful comparison is against the other cars in the Midsize Cars class for the same model year. The list below shows the highest-MPG peers, ranked from most to least efficient. Click any of them to open its full page.
The Chevrolet Corsica leads this group at 25 MPG, 12 MPG ahead of the 1990 Mercedes-Benz 420SE.
Specifications
The 1990 Mercedes-Benz 420SE runs a 4.2-liter 8-cylinder engine paired with a automatic 4-spd, sending power through rear-wheel drive.
Engine, transmission, and drivetrain together drive most of the variation in fuel economy across trims. A larger engine moves the car with less effort but burns more fuel. A turbo lets a small engine punch above its weight, often without much MPG penalty. All-wheel drive adds traction and weight, and usually costs a couple of MPG compared with two-wheel drive of the same engine.
- Vehicle class
- Midsize Cars
- Engine
- 4.2L 8-cylinder
- Transmission
- Automatic 4-spd
- Drivetrain
- Rear-Wheel Drive
- Fuel type
- Premium
- Annual petroleum use
- 22.9 barrels per year
- Gas guzzler tax
- Applies (federal)
Common questions about the 1990 Mercedes-Benz 420SE
Quick answers to the questions people most often search for when looking up the 1990 Mercedes-Benz 420SE.
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Is the 1990 Mercedes-Benz 420SE fuel efficient?
Not particularly. The 1990 Mercedes-Benz 420SE returns 13 combined MPG, which trails the average car in the Midsize Cars class for the same model year by about 29%. -
What MPG does the 1990 Mercedes-Benz 420SE get?
The EPA rates the 1990 Mercedes-Benz 420SE at 13 combined MPG, 12 MPG in city driving, and 15 MPG on the highway. Real-world numbers depend on your driving style, the weather, and how loaded the car is. -
How much does it cost to fuel a 1990 Mercedes-Benz 420SE per year?
The EPA estimates an annual fuel cost of $5,300 for the 1990 Mercedes-Benz 420SE. That figure assumes 15,000 miles of driving per year, a 55% city and 45% highway split, and the EPA's published average fuel price for the rated fuel grade. -
Does the 1990 Mercedes-Benz 420SE require premium gas?
Yes. The EPA lists the 1990 Mercedes-Benz 420SE as requiring premium gasoline. Running it on regular can reduce performance and may affect engine warranties, so it is not a recommended way to save at the pump. -
How much CO₂ does the 1990 Mercedes-Benz 420SE emit?
Tailpipe CO₂ emissions are 684 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 10,254 kilograms of CO₂. -
What is the difference between the city and highway MPG of the 1990 Mercedes-Benz 420SE?
City driving returns 12 MPG and highway driving returns 15 MPG, a gap of 3 MPG. The two figures are close enough that the car will hold its rated efficiency well across most driving patterns. -
What engine is in the 1990 Mercedes-Benz 420SE?
The 1990 Mercedes-Benz 420SE has a 4.2-liter 8-cylinder engine (EPA description: (GUZZLER) FFS MPFI (FFS)). -
What transmission and drivetrain does the 1990 Mercedes-Benz 420SE have?
The 1990 Mercedes-Benz 420SE comes with a automatic 4-spd transmission and rear-wheel drive. -
How does the 1990 Mercedes-Benz 420SE compare to the best car in its class?
The most efficient car in the Midsize Cars class for the 1990 model year is the Chevrolet Corsica at 24 combined MPG. The Mercedes-Benz 420SE returns 13 MPG, a gap of 11 MPG. If you are comparing on fuel economy alone, the class leader is worth a look. -
Does the 1990 Mercedes-Benz 420SE qualify for the gas guzzler tax?
Yes. The federal Gas Guzzler Tax applies to passenger cars rated below 22.5 combined MPG, and the 1990 Mercedes-Benz 420SE falls below that threshold. The tax is paid by the manufacturer at the point of sale and is built into the sticker price, so you will not see a separate line item at the dealership. Pickup trucks and SUVs are exempt from this tax even when their efficiency is lower.
Source: U.S. EPA fuel economy dataset. Annual fuel cost figures assume 15,000 miles of driving per year and a 55% city, 45% highway split. Real-world mileage varies with driving conditions, vehicle maintenance, fuel quality, and driver behaviour.