What does this cost in your state?
California is the costliest state and Arkansas the cheapest; each square shows that state's midpoint of the estimate.
Lower-cost states ($131)MiddleHigher-cost states ($167)
What it shows: CA is the highest at $167 and AR the lowest at $131, across 51 states.
Counts below are complaints filed with NHTSA, not failure rates: a longer bar means more owners reported it.
Is your car affected?
What it shows: The most common band for complaints about this repair is under 50,000 (46%), against 60% for all complaints: the biggest difference between the two.
What it shows: The most common band for complaints about this repair is 3-5 years (37%). The biggest difference from all complaints is under 3 years old: 28% against 40%.
Is it urgent, and what do owners notice first?
12,161 owner complaints name this part.
Owners say the dealer could not fix or repeat the problem. If it comes back after a repair, ask what was tested before you pay again.
Which trouble codes do owners report?
P0300 Random/Multiple Cylinder Misfire Detected leads at 81.
The code owners quote most is P0300. Read your own code from a scan and give the shop the exact code, not only "the light is on".
What do owners say it led to?
Among the 12,161 owner complaints naming this part, owners most often say engine damage followed.
If your car shows the signs above, get it checked before it gets as far as engine damage.
What did owners say they paid?
Half of the 661 owners who wrote a dollar amount gave $230 or less; one in ten wrote more than $3,900.
These are bills owners wrote down, often covering more than this one repair. They show how far a job can run; get written quotes for your own car.
How fast were owners driving when it happened?
55 mph or faster leads at 40%.
Owners reported it most often at highway speed. Tell the shop what speed it happens at, because that narrows the diagnosis.
How serious did it get for owners?
Among the 12,161 owner complaints naming this part, being towed is the outcome owners report most often.
What it shows: Towed is the largest at 851, followed by Crash reported at 454; the smallest shown is Death reported at 1.
Which model years show up most in the complaints?
Among the 12,161 owner complaints naming this part that state a model year, complaints cluster in a few model years instead of spreading evenly.
What it shows: 2017 is the largest at 1,755 (14%), followed by 2015 at 1,488 (12%); the smallest shown is 2025 at 368 (3%).
Do car diagnostic problems track monthly earnings of newly hired auto repair shop workers across states?
Across U.S. states, NHTSA owner complaints about car diagnostic run higher where monthly earnings of newly hired auto repair shop workers is higher, after adjusting for the makes sold in each state. This is an association across states, not proof that monthly earnings of newly hired auto repair shop workers causes this repair.
How to read it: Each dot is a state. Further right means more monthly earnings of newly hired auto repair shop workers (dollars); higher up means more complaints for this repair than expected (1.0 is average). If the dots climb to the right, reports of this repair rise with monthly earnings of newly hired auto repair shop workers (dollars).
What it shows: States with more monthly earnings of newly hired auto repair shop workers (dollars) tend to sit higher on the chart across 49 states: a pattern in the data, not proof of cause.
- The 10 states with the most monthly earnings of newly hired auto repair shop workers (District of Columbia, Massachusetts, Maryland, Washington, New Hampshire, Colorado, Rhode Island, Delaware, California, Oregon): reports of this repair run 6% above what the makes sold there would predict, and 6 of 10 are above expected. The 10 with the least (Utah, South Dakota, West Virginia, New Mexico, Mississippi, Alabama, Kansas, Louisiana, Wyoming, Iowa): 9% below, and 1 of 10 are above expected.
- Exceptions: Massachusetts, Washington and New Hampshire are among the highest in monthly earnings of newly hired auto repair shop workers but report below expected.
- Split the states into thirds: the third with the least monthly earnings of newly hired auto repair shop workers runs 5% below what the makes sold there would predict, the middle third 1% below, and the third with the most 7% above. It steps up steadily.
- For monthly earnings of newly hired auto repair shop workers, after allowing for the 1562 comparisons we ran, luck alone would produce a pattern this strong about 1 time in 10. Take out any single state and the monthly earnings of newly hired auto repair shop workers pattern still holds.
- Weak spot: compare only states with similar share of public road miles that are urban local streets and the pattern keeps about 6% of its strength, so part of it may come from share of public road miles that are urban local streets instead of monthly earnings of newly hired auto repair shop workers.
Higher starting pay for shop workers marks a tighter local labor market, which pushes up the labor part of every repair bill.
Do car diagnostic problems track median household income across states?
Across U.S. states, NHTSA owner complaints about car diagnostic run higher where median household income is higher, after adjusting for the makes sold in each state. This is an association across states, not proof that median household income causes this repair.
How to read it: Each dot is a state. Further right means more median household income (dollars); higher up means more complaints for this repair than expected (1.0 is average). If the dots climb to the right, reports of this repair rise with median household income (dollars).
What it shows: States with more median household income (dollars) tend to sit higher on the chart across 51 states: a pattern in the data, not proof of cause.
- The 10 states with the most median household income (District of Columbia, Maryland, Massachusetts, New Jersey, Hawaii, California, New Hampshire, Washington, Connecticut, Colorado): reports of this repair run 7% above what the makes sold there would predict, and 7 of 10 are above expected. The 10 with the least (Mississippi, West Virginia, Arkansas, Louisiana, Alabama, New Mexico, Kentucky, Oklahoma, South Carolina, Tennessee): 3% below, and 2 of 10 are above expected.
- Exceptions: Massachusetts, New Hampshire and Washington are among the highest in median household income but report below expected; South Carolina (20% above expected) is among the lowest but above expected.
- Split the states into thirds: the third with the least median household income runs 2% below what the makes sold there would predict, the middle third 1% above, and the third with the most 4% above. It steps up steadily.
- For median household income, after allowing for the 1562 comparisons we ran, luck alone would produce a pattern this strong about 1 time in 7. The median household income pattern leans on Hawaii: without it, it weakens.
- Weak spot: compare only states with similar cost of living index and the pattern keeps about 0% of its strength, so part of it may come from cost of living index instead of median household income.
Lower income means older cars kept longer and repairs put off until a part fails, which changes which repairs owners report.
How big and how well paid is the repair-shop market in my county?
Among 1,204 U.S. counties with 100 or more auto repair shop employees, average weekly pay in shops ran from $428 to $2,549 in 2024, a 6.0-to-1 spread (BLS QCEW and Census County Business Patterns, county level).
What it shows: Greenup is the largest at $2,549, followed by Marshall at $2,301; the smallest shown is Ponce Municipio at $428.
Can an independent shop get the same diagnostic data as the dealer?
Massachusetts requires car makers to sell owners and independent shops the same diagnostic and repair information they give dealers for model year 2002 and later, Maine added a standardized owner-authorized data platform from January 5, 2025, and the FTC reported to Congress in 2021 on how repair restrictions raise costs and limit choice.
| Where | Rule or report | What it requires or found |
|---|---|---|
| Federal | FTC report to Congress, May 2021 | Congress directed the FTC to examine how car and phone makers may limit repairs by consumers and repair shops and how those limits increase costs and limit choice. |
| Maine | 29-A M.R.S.A. 1810 (in force January 2025) | Since January 5, 2025, makers of vehicles with telematics sold in Maine must provide a standardized, owner-authorized access platform; owners can let an independent shop read the vehicle mechanical data. |
| Massachusetts | M.G.L. c.93K s.2 | Car makers selling in Massachusetts must sell owners and independent shops the same diagnostic and repair information they give their dealers (model year 2002 and later). |
| NCSL 2023 session list | Automotive right-to-repair bills | NCSL lists two Maine automotive right-to-repair measures in its 2023 session summary (H 1227 and IB 3), shown as pending. |
Who works in a repair shop and what do shops pay them?
Auto repair shops employed 240,230 service technicians in May 2024 at an average of $53,010 a year, while body and related repairers averaged $59,610, against $52,140 across all 1,029,850 shop jobs (BLS OEWS, national).
What it shows: General and Operations Managers is the largest at $90,830, followed by Automotive Service Technicians and Mechanics at $53,010; the smallest shown is Cleaners of Vehicles and Equipment at $32,610.
What do repair shop employees earn where you live?
Highest: WA ($53k). Lowest: WV ($39k).
Lower average pay ($39k)MiddleHigher average pay ($53k)
What it shows: WA is the highest at $53k and WV the lowest at $39k, across 51 states.
Has the maker published a fix?
A bulletin is a repair procedure a maker sends its dealers, not a safety defect: if your maker is listed, ask the dealer whether one covers your car and quote its number.
| Maker | Vehicles | Bulletin number | Date | What it says |
|---|---|---|---|---|
| Alfa Romeo | Giulia 2017–2022; Stelvio 2018–2022 | 22D Combo Rev1 | Sep 10, 2026 | Emissions recall 22D - on board diagnostics - dealer notification (revision. |
| Alfa Romeo | Stelvio 2018–2022; Giulia 2017–2022 | 22D Combo | Sep 2, 2026 | Emissions recall 22D - on board diagnostics. |
| Subaru | Solterra 2023–2026; Trailseeker 2026 and 1 more | 19-04-26 | Aug 14, 2026 | This Bulletin provided diagnostic procedure information to be followed when addressing Dark Current / Parasitic Draw concerns on Subaru EV vehicles. |
| Subaru | Solterra 2023–2026; Uncharted 2026 and 1 more | 15-334-25R | Jun 30, 2026 | This Bulletin outlines the diagnostic procedures to be followed when identifying dark current/parasitic draw concerns caused by third-party mobile applications on Solterra vehicles. |
| Subaru | Crosstrek 2020–2025; Outback 2020–2025 and 3 more | 16-159-26 | Jun 23, 2026 | This bulletin provides new diagnostic steps for DTC P0851 and P0852 to be used in conjunction with the applicable Service Manual. |
| BMW | X7 2023–2026; X1 2023–2026 and 11 more | B120326 | Jun 19, 2026 | Due to an implementation error in various OBD diagnostics in the vehicle's control units, in very rare cases itmay happen that stored fault memory codes (DTCs) and the MIL (warning light) are not automaticallydeleted even though the underlying malfunction has. |
54 more bulletins name this part; the car finder at the top checks yours, and the NHTSA bulletin file linked below lists them all.
What do owners say?
4 complaints quoted word for word, each with its NHTSA number.
They said they will charge me $125.00 diagnostic fee for it if they do not find any problem with it..
After charging us $175 for a diagnostic, they told us that they couldn't replicate the problem and no codes were stored in the computer so there was nothing they could do.
I once again have contacted nissan consumer affairs, who instructed me to take it to a different nissan repair facility and front the $99.00 diagnostic fee to have my vehicle diagnosed.
We can guess and pay $350 for the guess, or not guess and pay $125 for the diagnostics that were ran.
Check your car
A car diagnostic costs $79–$222 for a basic scan at a chain shop, according to the calculator above. The depth of the test moves the price most, and the shop type and the kind of car move it next.
What does a car diagnostic cost cover, and what does it leave out?
The fee buys a technician's time and equipment, not a repair. A basic scan reads the trouble codes stored in the car's computer. A standard diagnostic adds an inspection of the suspect system. An advanced pinpoint test uses tools such as an oscilloscope or a pressure test to prove which part has failed.
The estimate leaves out the repair itself, taxes, shop supply fees and any second diagnostic if the first one does not find the fault. A code is a starting point. It names a circuit or a system, not always the part to replace.
How much does each kind of diagnostic cost?
The calculator prices three test depths at a chain shop for a standard car, and three shop types for a basic scan. Find the row that matches the job you were quoted.
| Choice | Estimate |
|---|---|
| Independent shop, basic scan | $63–$190 |
| Chain shop, basic scan (default) | $79–$222 |
| Dealership, basic scan | $158–$317 |
| Chain shop, standard diagnostic | $150–$285 |
| Chain shop, advanced pinpoint | $222–$475 |
| SUV or truck, basic scan | $103–$288 |
| Luxury or performance car, basic scan | $103–$288 |
The dealership premium is about double the independent price for the same basic scan. Pinpoint testing costs more because it takes technician hours, not because the scanner is different.
How do you know which test you need?
Start with the symptom. A steady warning light with a car that drives normally usually needs a basic scan first. A light that comes and goes, a stall, a rough idle with no code, or a repair that did not fix the problem points to a standard or pinpoint test.
Urgency follows the symptom. A flashing warning light, loss of power or a stall on the road should not wait for the cheapest appointment. A steady light on a car that runs well can wait a few days, but driving for months on an unread code can turn a small repair into a larger one.
How do you get a fair quote for a diagnostic?
Ask four questions before you leave the car. What test depth does the price cover? Is there a time limit, and what happens past it?
Is the fee credited toward the repair? Will you get the codes and findings in writing?
Free scans at parts stores read the code number and nothing more. They are a fair first step, but they do not confirm which part failed. If a shop quotes a pinpoint test, ask what it expects to measure and why a standard test is not enough.
Compare any quote with the range for the test depth above, not with the basic scan range. A pinpoint quote near the top of its row is normal. A basic scan quote well above the chain-shop scan range deserves a question.
What does the estimate leave out?
The calculator does not know your shop's hourly rate, your car's wiring complexity or how hard an intermittent fault is to reproduce. Hybrids, diesels and late-model luxury cars often need manufacturer software, and that can raise the bill. Confirm the final number, and the time limit, with the shop before work starts.
Frequently asked questions
Is a diagnostic fee refundable if I get the repair done?
Often it is credited toward the repair at the same shop, but not always. Ask before you agree, and get the answer on the work order.
Can I skip the diagnostic and just replace the part the code names?
You can, but a code names a circuit or system, not always the failed part. Replacing parts on a guess can cost more than the diagnostic that would have confirmed the fault.
Sources
Data shown on this page
- NHTSA owner complaint file (2015-2019 · 2020-2024 · 2025-2026) file downloaded 2026-10-05
- NHTSA service bulletin file (2015-2019 · 2020-2024 · 2025-2026) file downloaded 2026-10-05
- CalcScrape calculator model scaled by BEA Regional Price Parities data from 2024
- Census LEHD Quarterly Workforce Indicators 2024, NAICS 8111, joined to NHTSA owner complaints file downloaded 2026-10-06
- U.S. Census Bureau, American Community Survey 5-year 2019-2023 (B19013), joined to NHTSA owner complaints file downloaded 2026-10-06
- BLS Quarterly Census of Employment and Wages 2024 (private, NAICS 8111) and Census County Business Patterns 2023 (NAICS 8111) file downloaded 2024 wages, 2023 counts
- Massachusetts General Laws c.93K s.2; Maine Secretary of State right-to-repair notice (29-A MRSA 1810); FTC report to Congress "Nixing the Fix" (May 2021 release); NCSL Right to Repair 2023 Legislation data from 2025
- BLS Occupational Employment and Wage Statistics, May 2024, industry Automotive Repair and Maintenance (NAICS 811100) file downloaded May 2024
- Census County Business Patterns (NAICS 8111) with BEA Regional Price Parities data from 2022
Terms: US government data, public domain.
Observed: records as filed; owner reports are unverified and are not failure rates. Modeled: our estimate, not a quote. Derived: computed from the records; an association, not a cause. Rule: a published legal rule, not a measurement; whether it covers a given repair depends on the car and the facts.
What is our own estimate
The price range comes from our calculator's formula. Its parts prices, labor hours per job and shop-rate tiers are CalcScrape estimates, not a published price dataset. Checked against RepairPal's range ($122–$179) on 2026-10-06: our default's midpoint is 0% above the middle of that range. Methodology