The light that came on after you filled up
A check engine light that appears a day or two after a fuel stop sends a lot of people into a small panic. Very often the cause is the least dramatic thing on the car: the fuel cap.
Modern vehicles run a system that captures fuel vapor from the tank instead of letting it escape into the air. The system periodically tests itself for leaks. A fuel cap that was not tightened until it clicked, a cap with a cracked seal, or a cap left hanging at the pump all look to that test like a leak, and the engine computer turns on the light.
Nothing is wrong with the engine. The light is reporting that the vapor system cannot hold its seal.
What to do
Check the cap. Remove it, look at the rubber seal for cracks or damage, put it back and tighten it until it clicks. Then drive normally.
The light does not go out the moment the cap is fixed. The system needs to run its self-test again, which can take several days of ordinary driving. If the light goes out on its own within that time, the cap was the cause.
If the light stays on after a week or so of driving, comes on with the engine running roughly, or flashes, it is something else, and the engine needs looking at properly. A cap is the first thing to rule out, never the only thing.
What to tell the store
When the light came on, whether it coincided with a fuel stop, whether you have already checked the cap, and anything the engine is doing differently. A light with no symptoms and a light with a rough idle are very different starting points.
Confirm the vehicle when you book. The national engine repair page covers what a warning light does and does not report. A fault that turns out to be overdue scheduled maintenance or the cooling system is handled in the same building.
Other stores nearby
Osage Beach and Springfield also offer engine repair in Missouri.
About this store
The Kansas City store runs sixteen services and is managed by Richard Kerber.
See the national engine repair page for all 33 locations.