Misfire or rough idle on the 2015 Subaru Wrx
Only 5 reports for this mode came with an odometer reading, which is too few for percentiles to mean anything. The page is here because someone linked to it; treat the figures as anecdotes, and see the full report for this year instead.
When misfire or rough idle gets reported
There are 6 reports of misfire or rough idle on the 2015 Subaru Wrx, 5 with a mileage attached. That is too few to place the failure on the odometer with any confidence.
A part like this is normally expected to survive 92,000 miles. It is the 3rd most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 10,500 miles | — | — |
Read the 10th percentile as “one report in ten arrived this early”. Exact figures are shown in this table because it is the table of record; everywhere else on the site they are rounded to the precision the sample can carry.
What a percentile can and cannot tell you here
These five numbers describe the readings owners gave, in order. The median is the middle one: half the reports arrived below it. The 10th and 90th are the edges of the bulk of the distribution, and the distance between them is the part worth reading. A tight spread — say 70,000 to 95,000 miles — points at something that wears out on a schedule, and the schedule is knowable. A wide one, 20,000 to 190,000, points at a fault that hits some cars and never troubles others, which means the mileage on the listing in front of you tells you very little about your odds.
What these figures are not is a survival curve. Every reading here comes from a car whose owner filed a complaint, so the sample contains only failures: it cannot say what share of the fleet made it past 150,000 miles untouched, because those owners had nothing to report. Nor is the mileage the moment of failure — it is the odometer reading as recalled at the time of filing, which may be weeks later and is sometimes rounded to the nearest ten thousand by the person typing it.
Percentiles are shown at all only once 8 readings exist for the vehicle and mode. Below that the middle of a handful of numbers is noise wearing a decimal point, so the figures are withheld rather than dressed up.
What happens, and what it costs
Putting it right typically runs $250–$1,600 at an independent US shop. That range is an editorial estimate held in this site's failure-mode catalogue, not a figure from NHTSA, and it is a repair cost rather than a diagnosis cost.
The same failure, every year of the Subaru Wrx
If one year stands out to the left, that is the year to avoid; if the whole line sits at a similar mileage, this is wear rather than a defect in one production run.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.
2015 wrx 2.0l manual transmission while driving the car in everyday situations I have had (3) distinct problems associated with the engine/throttle/idle. 1) ghost blip: when coming to a stop, around 5-15 MPH, put it in neutral coast to a stop idle will inexplicably spike from ~700rpm (idle) --> ~1.2-1.5k RPM (for a second or two...like a ghost blipped the throttle). No pressure applied to accelerator. 2) rough idle: while sitting at a stop, in neutral, ~700rpm (idle) --> will dip to ~650-600rpm for a fraction of second & reoccur every 2-4 seconds. Feels like someone lightly shaking your seat from left to right. 3) near stall: while sitting at a stop, in neutral, ~700rpm (idle) --> will dip the rpms low enough that the whole car noticeably shakes...similar to the shake you would experience if the engine were actually about to stall. The rpms will fumble around a bit and then hiccup back to normal idle after 4-5 seconds. All three items have been brought to the attention of the local subaru dealer on (2) occasions w/ the reply unable to diagnose problem and/or it is normal.
2015 wrx 2.0l manual transmission while driving the car in everyday situations I have had (3) distinct problems associated with the engine/throttle/idle. 1) ghost blip: when coming to a stop, around 5-15 MPH, put it in neutral coast to a stop idle will inexplicably spike from ~700rpm (idle) --> ~1.2-1.5k RPM (for a second or two...like a ghost blipped the throttle). No pressure applied to accelerator. 2) rough idle: while sitting at a stop, in neutral, ~700rpm (idle) --> will dip to ~650-600rpm for a fraction of second & reoccur every 2-4 seconds. Feels like someone lightly shaking your seat from left to right. 3) near stall: while sitting at a stop, in neutral, ~700rpm (idle) --> will dip the rpms low enough that the whole car noticeably shakes...similar to the shake you would experience if the engine were actually about to stall. The rpms will fumble around a bit and then hiccup back to normal idle after 4-5 seconds. All three items have been brought to the attention of the local subaru dealer on (2) occasions w/ the reply unable to diagnose problem and/or it is normal.
2015 wrx 2.0l manual transmission while driving the car in everyday situations I have had (3) distinct problems associated with the engine/throttle/idle. 1) ghost blip: when coming to a stop, around 5-15 MPH, put it in neutral coast to a stop idle will inexplicably spike from ~700rpm (idle) --> ~1.2-1.5k RPM (for a second or two...like a ghost blipped the throttle). No pressure applied to accelerator. 2) rough idle: while sitting at a stop, in neutral, ~700rpm (idle) --> will dip to ~650-600rpm for a fraction of second & reoccur every 2-4 seconds. Feels like someone lightly shaking your seat from left to right. 3) near stall: while sitting at a stop, in neutral, ~700rpm (idle) --> will dip the rpms low enough that the whole car noticeably shakes...similar to the shake you would experience if the engine were actually about to stall. The rpms will fumble around a bit and then hiccup back to normal idle after 4-5 seconds. All three items have been brought to the attention of the local subaru dealer on (2) occasions w/ the reply unable to diagnose problem and/or it is normal.
Also reported on the 2015 Subaru Wrx
Other powertrain problem
Other engine problem
Headlight failure or clouding
Complete engine failure or seizure
Excessive oil consumption
Differential or transfer case failure
How far this goes
This page is kept out of search results because 6 reports is not enough to publish percentiles from. It stays reachable because somebody looking at this exact car would rather see the reports than be told there are none.
Complaints are voluntary, so 6 is a floor and not a count of affected cars. Mileages are typed in by owners and cluster on round numbers. And the mode itself is assigned by software reading the complaint text, which is reliable in bulk and fallible one report at a time.
Questions this page answers
At what mileage does misfire or rough idle happen on the 2015 Subaru Wrx?
Across 5 owner reports that included an odometer reading, half were filed by 10,000 miles. A quarter were filed before — and a quarter after —. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is misfire or rough idle on the 2015 Subaru Wrx?
6 reports have been filed with NHTSA, about 0.7 per 1,000 vehicles. Complaints are voluntary, so this is a floor rather than a count of affected cars.
What this is and is not. These are the mileages at which owners chose to complain to a federal agency, which is not the same as the mileage at which the part fails on every car. It skews toward failures that happened outside warranty, cost real money, or frightened someone. It is still the only public dataset that carries failure mileage at all, and the shape of a few hundred readings is informative even when a single one is not. Methodology · JSON · this failure on other cars
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed