Car repair statistics 2026
What 87,623 car owners and mechanics asked in the last 12 months.
Most car repair statistics come from surveys or shop invoices. These come from the questions themselves. From November 10, 2025 through November 9, 2026, people asked MECH AI 452,740 questions in 176,195 conversations. This page reports what they asked about.
Every number is from MECH AI's own data. You are welcome to cite it. Please credit "MECH AI Repair Index 2026" and link to this page.
Key findings
- The 2026 MECH AI Repair Index found that the median vehicle people asked for repair help with was 16 years old.
- The 2026 MECH AI Repair Index found that 80.7% of repair conversations were about vehicles 10 or more years old.
- The 2026 MECH AI Repair Index found that Ford, Chevrolet and Toyota together made up 33.5% of repair conversations.
- The 2026 MECH AI Repair Index found that P0420 (catalytic converter efficiency) was the most asked-about trouble code, followed closely by P0300 (random misfire).
- The 2026 MECH AI Repair Index found that an oil and filter change was the most requested step-by-step repair guide.
How old are the cars people ask about?
Based on 174,654 conversations where the vehicle's model year was known.
- The median vehicle was 16 years old. The average was 16.6 years.
- 80.7% of conversations were about vehicles from model year 2016 or earlier (10 or more years old).
- 56.8% were about vehicles from model year 2011 or earlier (15 or more years old).
- 34.6% were about vehicles from model year 2006 or earlier (20 or more years old).
- Only 7.0% were about vehicles from model year 2021 or newer.
Which makes do people ask about most?
Share of the 176,195 repair conversations, by vehicle make.
| Rank | Make | Share of conversations | Average vehicle age |
|---|---|---|---|
| 1 | Ford | 12.1% | 18.1 years |
| 2 | Chevrolet | 11.0% | 17.6 years |
| 3 | Toyota | 10.4% | 15.9 years |
| 4 | Nissan | 6.2% | 16.3 years |
| 5 | Honda | 5.8% | 17.4 years |
| 6 | Volkswagen | 4.7% | 16.6 years |
| 7 | Dodge | 4.0% | 18.5 years |
| 8 | BMW | 3.6% | 16.4 years |
| 9 | Hyundai | 3.4% | 12.6 years |
| 10 | Jeep | 2.9% | 16.0 years |
- Among the ten most asked-about makes, Hyundai owners asked about the newest vehicles (12.6 years old on average) and Dodge owners the oldest (18.5 years).
A make's share reflects how many of its owners use MECH AI and how old their vehicles are. It is not a reliability ranking.
Which trouble codes do people ask about most?
Based on 7,691 conversations in which the user typed at least one powertrain trouble code (a "P" code).
| Rank | Code | What it means | Share of code conversations |
|---|---|---|---|
| 1 | P0420 | Catalyst efficiency below threshold, bank 1 | 7.8% |
| 2 | P0300 | Random or multiple cylinder misfire | 7.6% |
| 3 | P0171 | System too lean, bank 1 | 4.8% |
| 4 | P0301 | Cylinder 1 misfire | 2.7% |
| 5 | P0304 | Cylinder 4 misfire | 2.3% |
| 6 | P0430 | Catalyst efficiency below threshold, bank 2 | 2.2% |
| 7 | P0302 | Cylinder 2 misfire | 2.2% |
| 8 | P0303 | Cylinder 3 misfire | 1.9% |
| 9 | P0016 | Crankshaft and camshaft position correlation | 1.7% |
| 10 | P0174 | System too lean, bank 2 | 1.5% |
- Misfire codes (P0300 through P030C) appeared in 13.2% of code conversations.
- Catalytic converter codes (P0420 or P0430) appeared in 9.4% of code conversations.
- Evaporative emissions codes (P0440 through P0459) appeared in 6.5% of code conversations.
- Lean-condition codes (P0171 or P0174) appeared in 5.6% of code conversations.
- 29.8% of code conversations mentioned two or more different codes.
Most asked-about code by make
- Toyota: P0420, in 13.9% of 1,044 Toyota code conversations.
- Chevrolet: P0300, in 12.9% of 883 Chevrolet code conversations.
- Honda: P0420, in 12.7% of 433 Honda code conversations.
- Nissan: P0300, in 10.0% of 531 Nissan code conversations.
A trouble code points to a system, not a failed part. See the OBD2 code guide for what each code can mean.
Which repairs do people look up most?
Based on 18,639 step-by-step repair guides requested in MECH AI.
| Rank | Repair | Share of guides |
|---|---|---|
| 1 | Engine oil and filter change | 5.7% |
| 2 | Spark plug replacement | 3.8% |
| 3 | Front brake pad replacement | 3.5% |
| 4 | Serpentine belt replacement | 3.0% |
| 5 | Cabin air filter replacement | 1.6% |
| 6 | Battery replacement | 1.1% |
| 7 | Engine air filter replacement | 0.8% |
| 8 | Starter motor replacement | 0.7% |
| 9 | Alternator replacement | 0.5% |
- The four most requested guides (oil change, spark plugs, front brake pads and serpentine belt) made up 16.0% of all guides.
Methodology
- Source
- Anonymized, aggregated usage of the MECH AI app. No individual question, user or vehicle is identified.
- Period
- November 10, 2025 through November 9, 2026.
- Sample
- 452,740 questions in 176,195 conversations from 87,623 users worldwide. Internal and test accounts are excluded.
- Vehicle age
- 2026 minus the model year the user selected.
- Trouble codes
- Powertrain ("P") codes typed into a question. A conversation is counted once per code. Codes read by a scan tool are not included.
- Repair guides
- One guide per owner, vehicle and repair. Opening the same guide again does not add to the count.
- What this is not
- A survey of all vehicles on the road. It describes what MECH AI users asked about, so it over-represents older vehicles and owners who do their own repairs. It does not measure how reliable any make is.