Said It Here

Will custom modifications like a flat bed pass safety inspection?

Vehicle modifications and emission monitor readiness issues can cause unexpected failures during official safety certifications. When sensors like the catalyst, evap system, and O2 sensor show as not ready, or when custom parts like a homemade flat bed are installed, owners struggle to determine if their vehicle will pass inspection.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Consulting local inspection guidelines
  2. 2
    Asking mechanics for opinions on legality
  3. 3
    Completing a specific drive cycle
  4. 4
    Checking sensors at an auto parts store

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/MechanicAdvice2 people · September 2026

“Will a pickup truck that has a custom/homemade flat bed have any issues passing Ontario safety certification?”source ↗

Ten_Lug_Thug · r/MechanicAdvice · 2 upvotes

“I passed everything on emissions testing but “monitors ready” I went to autozone to see what sensors were not ready, and none appeared.”source ↗

“I specifically have the sensors: Catalyst, Evap Sys, 02 Sensor NOT ready.”source ↗

blackharlotteyork · r/MechanicAdvice · 1 upvotes

Where this came up

People with this problem also raised