---
title: "Carb Tester — Clean Truck Check, Sonoma, CA | CTC Finder"
description: "Carb Tester in Sonoma, CA is on CARB's Clean Truck Check tester list. Offers mobile testing, OBD testing, motorhome testing. Phone, address and nearby testers."
url: "https://ctcfinder.com/tester/carb-tester-sonoma/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Carb Tester

Clean Truck Check tester in Sonoma, CA (Sonoma County).

> CTC Finder is an independent directory, not affiliated with CARB. Tester data: CARB Clean Truck Check public tester list, last checked November 1, 2026. Confirm services, hours and prices with the tester.

| Field | Value |
|---|---|
| Location | 21707 8th St E, Sonoma, CA 95476 |
| County | Sonoma County |
| Phone | (707) 772-9077 |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | No |
| Motorhomes | Yes |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Carb Tester can test

| Your vehicle | Test required | This tester |
|---|---|---|
| Diesel, model year 2013 or newer | OBD scan | Yes |
| Alternative fuel (natural gas, propane), 2018 or newer | OBD scan | Yes |
| Diesel, model year 2012 or older (no OBD) | Smoke opacity test (SAE J1667) plus visual inspection | Not listed |
| California-registered motorhome | Same test as above by engine year, once a year | Yes |

For a 2012 or older diesel, the nearest listed tester with smoke opacity testing is Faustino in Sonoma, about 1 mile away. [See listing](https://ctcfinder.com/tester/faustino-sonoma/).

## Clean Truck Check testers in Sonoma County

Carb Tester is one of 28 testing businesses in Sonoma County on CARB's public tester list. 19 of them offer mobile testing and 14 do smoke opacity tests. In Sonoma itself there are 5 listed businesses, 4 of them mobile.

## 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](https://ctcfinder.com/guide/deadlines-2026-2027/). You can test up to 90 days before a deadline. Free email reminders: https://ctcfinder.com/reminders/

## Frequently asked questions

### Does Carb Tester offer mobile Clean Truck Check testing?

Yes. Carb Tester 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 Carb Tester test a 2012 or older diesel truck?

Carb Tester does not list smoke opacity testing, which older non-OBD diesel trucks need. The nearest listed tester that does is [Faustino](https://ctcfinder.com/tester/faustino-sonoma/) (about 1 mile). Trucks from 2013 on get an OBD scan instead.

### How much does Carb Tester charge for a Clean Truck Check?

Carb Tester has not published prices with us; call (707) 772-9077 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](https://ctcfinder.com/guide/cost/).

### Is Carb Tester a CARB-credentialed tester?

Carb Tester 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 nearby

- **[Faustino](https://ctcfinder.com/tester/faustino-sonoma/)** — 23195 Maffei Rd, Sonoma, CA 95476 — (707) 953-3466 — 1 mi. Services: mobile testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Manzoni Inc](https://ctcfinder.com/tester/manzoni-inc-sonoma/)** — 27500 Skaggs Island Rd, Sonoma, CA 95476 — (707) 996-3685 — 1 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Serres corp----CLAYTON](https://ctcfinder.com/tester/serres-corp-clayton-sonoma/)** — 510 Chase St, Sonoma, CA 95476 — (707) 934-7097 — 1 mi. Services: OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Shreddy Transport LLC](https://ctcfinder.com/tester/shreddy-transport-llc-sonoma/)** — 1270 Bragg St, Sonoma, CA 95476 — (707) 227-4492 — 1 mi. Services: mobile testing, OBD testing.
- **[Aaron Ramo](https://ctcfinder.com/tester/aaron-ramo-napa/)** — Napa, CA 94559 — (707) 225-7982 — 9 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Jones Family Mobile Diesel Repair](https://ctcfinder.com/tester/jones-family-mobile-diesel-repair-napa/)** — 933 Water St, Napa, CA 94559 — (410) 301-8518 — 9 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.