Who usually needs it
Older diesel without the OBD Clean Truck Check path — often pre-2013 engines needing opacity + visual inspection.
San Diego County service page
Mobile OVI / smoke opacity testing
Opacity and visual inspection path for diesel that is not on the HD-OBD route — commonly 2012 and older. We bring calibrated opacity equipment to your yard.
What OVI / smoke covers
San Diego County rates on this site (OBD $119 · OVI $219). Northern California → norcalcarbmobile.com.
What we do on site
SAE J1667-style snap-acceleration opacity testing with calibrated gear, plus the visual emissions-control check dispatch confirms for your unit.
How to prep
Safe acceleration space, accessible exhaust path, VIN/plate ready, and trucks warmed if needed. Multi-truck yards are ideal for one visit.