Do fuel injector replacement problems track solo operators as a share of all auto repair businesses across states?
Across U.S. states, NHTSA owner complaints about fuel injector replacement 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.
State reports of this repair against solo operators as a share of all auto repair businesses, one dot per stateEach dot is a state: how much more (or less) than expected this repair is reported there, adjusted for the makes sold in the state, against its solo operators as a share of all auto repair businesses
How to read it: Each dot is a state. Further right means more solo operators as a share of all auto repair businesses; 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 solo operators as a share of all auto repair businesses.
What it shows: States with more solo operators as a share of all auto repair businesses tend to sit higher on the chart across 38 states: a pattern in the data, not proof of cause.
Data: Census Nonemployer Statistics 2021 and County Business Patterns 2023, NAICS 8111, joined to NHTSA owner complaints, downloaded 2026-10-06 · 38 states. Chart: CalcScrape · calcscrape.com
The 10 states with the most solo operators as a share of all auto repair businesses (Mississippi, Georgia, Florida, Texas, Louisiana, Arkansas, Tennessee, Alabama, Kentucky, South Carolina): reports of this repair run 18% above what the makes sold there would predict, and 8 of 10 are above expected. The 10 with the least (Massachusetts, Washington, Connecticut, New York, New Hampshire, New Jersey, Oregon, Minnesota, Utah, Wisconsin): 1% below, and 4 of 10 are above expected.
Exceptions: Florida and Arkansas are among the highest in solo operators as a share of all auto repair businesses but report below expected; Utah (89% above expected) and Wisconsin (62% above expected) are among the lowest but above expected.
Split the states into thirds: the third with the least solo operators as a share of all auto repair businesses runs 2% above what the makes sold there would predict, the middle third 7% below, and the third with the most 20% above. Most of the solo operators as a share of all auto repair businesses effect sits in the third with the most.
For solo operators as a share of all auto repair businesses, after allowing for the 1562 comparisons we ran, luck alone would produce a pattern this strong about 1 time in 30. Take out any single state and the solo operators as a share of all auto repair businesses pattern still holds.
Weak spot: compare only states with similar median household income and the pattern keeps about 30% of its strength, so part of it may come from median household income instead of solo operators as a share of all auto repair businesses.
Where more repair work is done by one-person operators with low overhead, prices and the kinds of repairs done differ from chain and dealer shops.