Yolo Smog

Clean Truck Check tester in Woodland, CA (Yolo County).

Yolo Smog appears on CARB's public list of credentialed Clean Truck Check testers. It lists mobile testing, OBD testing, motorhome testing. Mobile testing means the tester can come to your yard or job site.

Location
374 W Main St, Woodland, CA 95695
County
Yolo County
Phone
(530) 383-9330
Mobile testing
Yes — comes to your yard
OBD testing
Yes
Smoke opacity (non-OBD)
No
Motorhomes
Yes
Credentialed testers
1
Last verified

Call (530) 383-9330 Open in Google Maps

Before you call

  • Have your VIN, odometer reading and plate number ready.
  • Your vehicle must be registered in CTC-VIS and the annual compliance fee paid; the tester submits the result to CARB.
  • Ask for the price per vehicle and any mobile trip fee. Typical published prices for an OBD test are $50–$135 per vehicle (see cost guide).

Which trucks Yolo Smog can test

The test CARB requires depends on the engine's fuel and model year. Based on the services Yolo Smog lists on CARB's tester list:

Your vehicleTest requiredThis tester
Diesel, model year 2013 or newerOBD scanYes
Alternative fuel (natural gas, propane), 2018 or newerOBD scanYes
Diesel, model year 2012 or older (no OBD)Smoke opacity test (SAE J1667) plus visual inspectionNot listed
California-registered motorhomeSame test as above by engine year, once a yearYes

For a 2012 or older diesel, the nearest listed tester with smoke opacity testing is Paul Mendoza in Woodland, about 1 mile away. See listing.

Clean Truck Check testers in Yolo County

Yolo Smog is one of 42 testing businesses in Yolo County on CARB's public tester list. 36 of them offer mobile testing and 23 do smoke opacity tests. In Woodland itself there are 12 listed businesses, 11 of them mobile. All testers in Yolo County.

When your truck is due

Most trucks test twice a year, on a schedule tied to the DMV registration expiration date. CARB says OBD trucks move to four tests a year beginning October 2027. California-registered (non-commercial) motorhomes and agricultural vehicles test once a year. See the deadline guide. You can test up to 90 days before a deadline. Get a free email reminder before each one.

How to check a tester's credential

CARB publishes its Clean Truck Check tester list, where Yolo Smog appears as of November 1, 2026. Listing there is optional, so a missing name does not always mean a tester is not credentialed. After the test, check that the passing result shows for your vehicle in CTC-VIS; that is what counts for compliance.

Frequently asked questions

Does Yolo Smog offer mobile Clean Truck Check testing?

Yes. Yolo Smog says on CARB's tester list that it offers mobile testing, so it can come to your yard or job site. Ask about a trip fee when you call.

Can Yolo Smog test a 2012 or older diesel truck?

Yolo Smog does not list smoke opacity testing, which older non-OBD diesel trucks need. The nearest listed tester that does is Paul Mendoza (about 1 mile). Trucks from 2013 on get an OBD scan instead.

How much does Yolo Smog charge for a Clean Truck Check?

Yolo Smog has not published prices with us; call (530) 383-9330 for a quote. Published California prices are usually $50–$135 per vehicle for an OBD test and $190–$200 for a smoke opacity test, plus CARB's annual fee ($32.13 in 2026). See the cost guide.

Is Yolo Smog a CARB-credentialed tester?

Yolo Smog appears on CARB's public Clean Truck Check tester list, last checked November 1, 2026. Only credentialed testers can submit results to CARB; after the test, confirm the passing result shows for your vehicle in CTC-VIS.

Other testers near Woodland

Source: CARB's public Clean Truck Check tester list, last checked . Listing on CARB's list is optional for testers, so some credentialed testers are not shown. Services, hours and prices change; please confirm with the tester before you go. Something wrong? Send a correction.

Call (530) 383-9330