Research · Minicompact Cars
2021 Porsche 911 Carrera 4 CabrioletRecalls, problems, MPG & safety
NHTSA lists 0 safety recalls and 5 owner complaints for the 2021 Porsche 911 Carrera 4 Cabriolet. Most complaints involve fuel/propulsion system (3) and equipment adaptive/mobility (1). The EPA rates it 20 mpg combined.
Combined MPG
20mpg
EPA · 1 version
NHTSA overall
—
Not rated by NCAP
Safety recalls
0campaigns
NHTSA
Owner complaints
5
Top: fuel/propulsion system
Fuel cost / yr
$3,850est.
EPA estimate, best version
Safety recalls
NHTSA campaigns for this model year
0 recalls found in NHTSA data for the 2021 Porsche 911 Carrera 4 Cabriolet as of Nov 11, 2026.
Data from NHTSA Recalls API · synced Nov 11, 2026NHTSA vehicle page
Owner complaints by component
5 complaints filed with NHTSA · May 2021 – Mar 2026
- Fuel/propulsion system3
- Equipment adaptive/mobility1
- Seats1
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.
Data from NHTSA Complaints API · synced Nov 11, 2026NHTSA vehicle page
What owners report most
Verbatim excerpts from NHTSA complaints, by component
Fuel/propulsion system
3 reports1 fire
“The fuel injection problem on cylinder 2 and 4 had injector electrical faults for the last two years resulting in reduced power warning. I finally took my car to the dealer for an analysis. After their analysis here is their statement on the service invoice: "Client state check engine light comes on and vehicle will run rough - Client scan for codes and had codes P0202 & P0204. Cylinder 2 and 4 fuel injector electrical faults. After updating DME software, clearing faults and test driving, mil illuminated again. Quoted fuel injector replacement. Due to the large amount of labor required for replacement, all 6 have been quoted to circumvent a potentially bad batch and to prevent a re-visit to replace any additional injectors at a later date." I had to pay almost $11,000 to replace "bad batch" injectors on a car that has only 13,455 miles. If they are "bad" injectors, is this a wider problem than my vehicle?”
Equipment adaptive/mobility
1 report
“2021 Porsche 911. Consumer writes in regards to missing computer chip for proper steering.”
Seats
1 report
“THE SEAT BACK RELEASE ON BOTH SEATS IS VERY HARD TO PULL. ON THE DRIVERS SIDE THE STRAP BROKE FREE WHILE ATTEMPTING TO EXIT AND THE SEAT WOULD NOT RELEASE. THIS COULD BE A SAFETY DANGER IN A CRASH WHEN REAR SEAT OCCUPANTS WOULD NOT BE ABLE TO EXIT”
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 11, 2026
Engines, transmissions & drive
1 version rated by the EPA
- EPA class
- Minicompact Cars
- Engines
- 3.0L 6-cyl turbo
- Transmissions
- Automatic (AM-S8)
- Drive
- All-Wheel Drive
- Fuel
- Premium Gasoline
Towing, payload and dimensions aren’t in the EPA or NHTSA data, so we don’t list them.
Data from EPA fueleconomy.gov · synced Nov 11, 2026EPA listing
EPA fuel economy by version
City / highway / combined, annual fuel cost and CO₂
EPA
| Version | City | Hwy | Comb. | Fuel / yr | CO₂ g/mi |
|---|---|---|---|---|---|
| 911 Carrera 4 Cabriolet Auto (AM-S8), 6 cyl, 3.0 L, Turbo · All-Wheel Drive | 18 | 24 | 20 | $3,850 | 443 |
- 20mpg comb.
Data from EPA fueleconomy.gov · synced Nov 11, 2026 · Fuel cost is EPA’s annual estimate (15,000 mi, 55% city)
NHTSA 5-Star Safety Ratings
1 tested variant
NHTSA has not published 5-Star Safety Ratings for the 2021 Porsche 911 Carrera 4 Cabriolet as of Nov 11, 2026.
Data from NHTSA NCAP Safety Ratings API · synced Nov 11, 2026Vehicle 15743
Maintenance basics
General guidance, not the OEM schedule. Check your owner’s manual.
General guidance
| Item | Miles | Time | Note |
|---|---|---|---|
| Engine oil & filter | 5,000–10,000 mi | 6–12 months | Follow the oil-life monitor if fitted |
| Tire rotation | 5,000–7,500 mi | Every oil change | Check pressure monthly |
| Engine air filter | 15,000–30,000 mi | 1–2 years | Sooner in dusty areas |
| Cabin air filter | 15,000–25,000 mi | 1–2 years | |
| Brake fluid | — | 2–3 years | Absorbs moisture over time |
| Coolant | 60,000–100,000 mi | 5–10 years | Long-life coolants last longer |
| Spark plugs | 60,000–100,000 mi | — | Iridium/platinum plugs at the long end |
| 12V battery | — | 3–5 years | Heat shortens battery life |
- Engine oil & filter5,000–10,000 mi
6–12 months - Tire rotation5,000–7,500 mi
Every oil change - Engine air filter15,000–30,000 mi
1–2 years - Cabin air filter15,000–25,000 mi
1–2 years - Brake fluid—
2–3 years - Coolant60,000–100,000 mi
5–10 years - Spark plugs60,000–100,000 mi
— - 12V battery—
3–5 years
Typical intervals for modern cars. Severe service (towing, short trips, extreme heat or cold) shortens them.
2021 911 Carrera 4 Cabriolet questions
How many recalls does the 2021 Porsche 911 Carrera 4 Cabriolet have?
0 recalls found in NHTSA data as of Nov 11, 2026.
What are the most common 2021 Porsche 911 Carrera 4 Cabriolet problems?
Owners filed 5 complaints with NHTSA. The most-cited components are fuel/propulsion system (3), equipment adaptive/mobility (1), seats (1). Complaints are unverified owner reports and aren't adjusted for how many cars were sold.
What MPG does the 2021 Porsche 911 Carrera 4 Cabriolet get?
The EPA rates the 2021 Porsche 911 Carrera 4 Cabriolet at 20 mpg combined, depending on engine and drivetrain (1 version rated).
Data from NHTSA & EPA · synced Nov 11, 2026