Missouri emissions inspection: OBD readiness rules
Gateway Vehicle Inspection Program plugs into the car's OBD2 port and checks its readiness monitors, the self-tests the engine module runs while you drive. Here's how many may still be not ready.
| Monitors allowed not ready | 1996 to 2000: 2 not ready 2001 to 2022: 1 not ready |
|---|---|
| Check-engine light on | Fails |
| Model years tested in 2026 | 1996 to 2022 |
| Where | St. Louis area |
Catalyst and oxygen sensor monitors must be supported; no readiness waivers.
Official source: Gateway Vehicle Inspection Program (checked October 6, 2026). States change their rules; check there before you go.
Check your BMW before you go
In the AutoLingo for BMW app, pick Missouri under Settings, "State for emissions testing". Connect, and the Overview's "Inspection in Missouri" line says whether the car would pass, would not pass, or isn't tested, with the reason (for example, which monitor isn't ready). Step by step: check if your BMW is ready for an emissions inspection.
Monitors not ready? Follow BMW's drive cycle (about 25 minutes from a cold start), or drive normally for a few days, city and highway, and check again. They reset when the battery is disconnected or the fault codes are cleared, so don't clear codes just before the test.
Coming soon
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