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 ($351)MiddleHigher-cost states ($447)
What it shows: CA is the highest at $447 and AR the lowest at $351, 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 50,000-100,000 (44%). The biggest difference from all complaints is under 50,000: 38% against 60%.
What it shows: The most common band for complaints about this repair is 6-9 years (40%). The biggest difference from all complaints is under 3 years old: 22% against 40%.
Is it urgent, and what do owners notice first?
882 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?
P0301 Cylinder 1 Misfire Detected leads at 9.
The code owners quote most is P0301. 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 882 owner complaints naming this part, owners most often say loss of power followed.
What owners say happened after the problem. Loss of power: 56 (6%); Engine damage: 36 (4%); Stalled while driving: 18 (2%).
If your car shows the signs above, get it checked before it gets as far as loss of power.
Which other parts do owners name in the same complaint?
Among the 882 owner complaints naming this part, spark plug is named in 10% of them, more than any other part.
Owners name the spark plug most often in the same complaint, which is not proof that one caused the other. Ask the shop whether it checked the spark plug too, so you are not quoted twice for one visit.
How fast were owners driving when it happened?
55 mph or faster leads at 33%.
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 882 owner complaints naming this part, being towed is the outcome owners report most often.
What it shows: Towed is the largest at 26, followed by Crash reported at 2; the smallest shown is Fire reported at 1.
Which model years show up most in the complaints?
Among the 882 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 206 (23%), followed by 2015 at 108 (12%); the smallest shown is 2025 at 10 (1%).
Do rough idle repair problems track registered cars and trucks per resident across states?
Across U.S. states, NHTSA owner complaints about rough idle repair run higher where registered cars and trucks per resident is higher, after adjusting for the makes sold in each state. This is an association across states, not proof that registered cars and trucks per resident causes this repair.
How to read it: Each dot is a state. Further right means more registered cars and trucks per resident; 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 registered cars and trucks per resident.
What it shows: States with more registered cars and trucks per resident tend to sit higher on the chart across 28 states: a pattern in the data, not proof of cause.
- The 9 states with the most registered cars and trucks per resident (Arkansas, Alabama, Kentucky, Michigan, South Carolina, Oregon, Tennessee, Wisconsin, Ohio): reports of this repair run 17% above what the makes sold there would predict, and 8 of 9 are above expected. The 9 with the least (New York, New Jersey, Massachusetts, Texas, Connecticut, California, Maryland, Illinois, North Carolina): 4% below, and 3 of 9 are above expected.
- Exceptions: Wisconsin is among the highest in registered cars and trucks per resident but reports below expected.
- Split the states into thirds: the third with the least registered cars and trucks per resident runs 4% below what the makes sold there would predict, the middle third 14% above, and the third with the most 17% above. Most of the registered cars and trucks per resident effect sits between the lowest and the middle third.
- For registered cars and trucks per resident, after allowing for the 1562 comparisons we ran, luck alone would produce a pattern this strong about 1 time in 129. Take out any single state and the registered cars and trucks per resident pattern still holds.
- Weak spot: compare only states with similar auto repair shops per 100,000 registered vehicles and the pattern keeps about 37% of its strength, so part of it may come from auto repair shops per 100,000 registered vehicles instead of registered cars and trucks per resident.
- For registered cars and trucks per resident, of the 4 exception states, 1 read the same way for the other parts of the system (so that is the system there, not this repair) and 3 are specific to this repair.
More registered vehicles per resident means more cars on the road and more older vehicles kept in service.
Do rough idle repair problems track quarterly job separations as a share of auto repair shop employment across states?
Across U.S. states, NHTSA owner complaints about rough idle repair run higher where quarterly job separations as a share of auto repair shop employment is higher, after adjusting for the makes sold in each state. This is an association across states, not proof that quarterly job separations as a share of auto repair shop employment causes this repair.
How to read it: Each dot is a state. Further right means more quarterly job separations as a share of auto repair shop employment; 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 quarterly job separations as a share of auto repair shop employment.
What it shows: States with more quarterly job separations as a share of auto repair shop employment tend to sit higher on the chart across 27 states: a pattern in the data, not proof of cause.
- The 9 states with the most quarterly job separations as a share of auto repair shop employment (Colorado, South Carolina, Tennessee, Georgia, Alabama, Arizona, Texas, Florida, North Carolina): reports of this repair run 16% above what the makes sold there would predict, and 8 of 9 are above expected. The 9 with the least (Massachusetts, Pennsylvania, New York, Illinois, California, Wisconsin, Maryland, New Jersey, Connecticut): 5% below, and 3 of 9 are above expected.
- Exceptions: Texas is among the highest in quarterly job separations as a share of auto repair shop employment but reports below expected.
- Split the states into thirds: the third with the least quarterly job separations as a share of auto repair shop employment runs 5% below what the makes sold there would predict, the middle third 8% above, and the third with the most 16% above. It steps up steadily.
- For quarterly job separations as a share of auto repair shop employment, after allowing for the 1562 comparisons we ran, luck alone would produce a pattern this strong about 1 time in 38. Take out any single state and the quarterly job separations as a share of auto repair shop employment pattern still holds.
- Weak spot: compare only states with similar auto repair shops per 100,000 registered vehicles and the pattern keeps about 49% of its strength, so part of it may come from auto repair shops per 100,000 registered vehicles instead of quarterly job separations as a share of auto repair shop employment.
- For quarterly job separations as a share of auto repair shop employment, of the 4 exception states, 2 read the same way for the other parts of the system (so that is the system there, not this repair) and 2 are specific to this repair.
Where shops lose and replace workers faster, fewer experienced technicians are available, which changes how repairs are diagnosed and redone.
Do rough idle repair problems track solo operators as a share of all auto repair businesses across states?
Across U.S. states, NHTSA owner complaints about rough idle repair run higher where solo operators as a share of all auto repair businesses is higher, after adjusting for the makes sold in each state. This is an association across states, not proof that solo operators as a share of all auto repair businesses causes this repair.
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 |
|---|---|---|---|---|
| Jeep | Grand Cherokee L 2021–2024; Grand Cherokee 4xe 2021–2024 and 4 more | 09-018-25 | Jul 16, 2025 | Engine Cylinder Block Porosity Inspection - Engine Cold Start Rough Idle Customers may experience the following: Rough engine idle when cold starting the engine. |
| Chrysler | Voyager 2020–2025; Pacifica 2018–2025 | 09-011-25 | May 18, 2025 | "Misfire Diagnostic Trouble Codes (DTCs), Rough Idle, Valvetrain Noise Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): P0301 - Cylinder 1. |
| RAM | Promaster 2022–2025; 1500 2019–2025 | 9100498 Rev 3 | May 12, 2025 | 3.6L PSU Long Block Misfire DTC codes and/or rough idle and/or valvetrain noise. |
| Jeep | Wrangler 2018–2025; Wagoneer 2022–2025 and 5 more | S2509000004 | Apr 2, 2025 | Misfire dtcs, rough idle, valvetrain. |
| Chevrolet | Equinox 2025 | PIP6042A | Apr 2, 2025 | This Preliminary Information communicates a intermittent rough idle on initial cold start and potential CEL/SES Light more on inclement weather and Engineering is investigating. |
| Jeep | Grand Cherokee 2016–2024; Grand Cherokee 4xe 2021–2024 and 3 more | 9100498 | Feb 10, 2025 | "3.6L PSU Long Block Misfire DTC codes and/or rough idle and/or valvetrain noise. |
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.
November 2021 vehicle exhibits rough idle, multiple dashboard warning lights/messages come on with mileage at approximately 13,000 miles.
Engine also burns about 1 quart of oil every 7000 miles and often has a rough idle, with very rough idle periodically.
Vehicle started having rough idle at about 70,000 miles when air conditioner would be turned on.
My 2016 ford fusion se has 14,499 miles and dies at red lights, idles rough when ac in on and has died while driving 30 mph.
Check your car
A rough idle is a symptom, not a part, so the cause you end up paying for moves that number more than anything else.
What does a rough idle repair price cover?
The estimate covers one repair for one cause: the part, if there is one, and the labor to fit it at the hourly rate of the shop type you pick. It does not cover finding the cause. A shop that has to scan codes, check for vacuum leaks and test the ignition will usually charge a diagnostic fee first, and that fee sits outside the range.
It also does not cover a second fault. If the first repair does not smooth the idle, the next one is a new line on the bill.
How much does the cause change the price?
Here are the calculator's ranges, changing one setting at a time from the default.
| Setting | Estimate |
|---|---|
| Default: spark plugs | $224–$584 |
| Throttle body cleaning | $146–$256 |
| Fuel injector cleaning | $196–$356 |
| Idle air control (IAC) valve | $214–$414 |
| Mass airflow (MAF) sensor | $246–$556 |
| Independent shop (about $100/hr) | $200–$545 |
| Dealership (about $175/hr) | $290–$691 |
| SUV or truck | $248–$689 |
Cleaning a throttle body or injectors is the cheap end, and it is a reasonable first step when the shop finds carbon buildup. A sensor or valve is a replacement, so it costs more. Larger engines and trucks cost more because there is more to reach and more plugs to change.
How do I know how urgent it is?
Read the check engine light first. A solid light with a mild shake can usually wait a few days for an appointment. A flashing light with the engine shaking hard points to a misfire, and unburned fuel can overheat the catalytic converter, which costs far more than a plug or a coil. Get that read the same day if you can, and avoid long trips until you do.
A faint vibration only on a cold start is the least urgent case. Mention it at your next service rather than rushing a repair.
How do I get a fair quote?
Give two or three shops the same details: year, make, model, engine size, whether the light is solid or flashing, and any code you already have. Ask what the diagnostic fee is and whether it is credited if you approve the repair. Ask the shop to name the cause it found, not just a part, and to show you the evidence, such as the code or the cracked hose.
Compare quotes for the same cause. A throttle body cleaning quote and a MAF sensor quote are different jobs, so a gap between them is not a bargain.
What does the estimate leave out?
It is a range for a typical engine, not a quote for yours. Plugs buried under an intake manifold take more labor than plugs on top. A vacuum leak is cheap in parts but can cost real labor to find, and the calculator does not price the hunt.
If a quote lands well above the range for the same cause and shop type, ask what is being added before you pay. The next step is to enter your vehicle and shop type in the calculator and take that range with you.
Frequently asked questions
Can I clean the throttle body myself?
Many owners do, since it is the cheapest cause on the list. Follow the cleaner's directions, and do not force the throttle plate open on an electronic throttle.
Should I replace spark plugs and ignition coils together?
Only if the coil tests bad. Ask the shop to test the coils rather than replacing them by default.
Is the dealership worth the higher price?
Its hourly rate is higher, so the total is higher. Pay it only if the cause is a manufacturer-specific fault, and ask your dealer whether a bulletin applies.
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
- FHWA Highway Statistics 2023 Table MV-1 with Census 2023 population, joined to NHTSA owner complaints file downloaded 2026-10-06
- Census LEHD Quarterly Workforce Indicators 2024, NAICS 8111, joined to NHTSA owner complaints file downloaded 2026-10-06
- Census Nonemployer Statistics 2021 and County Business Patterns 2023, NAICS 8111, joined to NHTSA owner complaints file downloaded 2026-10-06
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.
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. Not independently checked: no established price guide publishes a general range for this exact job (looked 2026-10-06), so the default has no outside comparison. Methodology