---
title: "Oscar Diaz — Clean Truck Check, Los Angeles, CA | CTC Finder"
description: "Oscar Diaz in Los Angeles, CA is on CARB's Clean Truck Check tester list. Offers OBD testing. Phone, address and nearby testers."
url: "https://ctcfinder.com/tester/oscar-diaz-los-angeles/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Oscar Diaz

Clean Truck Check tester in Los Angeles, CA (Los Angeles 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 | Los Angeles, CA 90002 |
| County | Los Angeles County |
| Phone | (330) 409-9181 |
| Mobile testing | No |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | No |
| Motorhomes | No |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Oscar Diaz 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 | Not listed |

For a 2012 or older diesel, the nearest listed tester with smoke opacity testing is Absolute Inspections in Los Angeles, about 2 miles away. [See listing](https://ctcfinder.com/tester/absolute-inspections-los-angeles/).

If you need a tester at your yard, the nearest listed tester that offers mobile testing is Full Port Diagnostics in Los Angeles, about 1 mile away. [See listing](https://ctcfinder.com/tester/full-port-diagnostics-los-angeles/).

## Clean Truck Check testers in Los Angeles County

Oscar Diaz is one of 516 testing businesses in Los Angeles County on CARB's public tester list. 465 of them offer mobile testing and 190 do smoke opacity tests. In Los Angeles itself there are 69 listed businesses, 60 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 Oscar Diaz offer mobile Clean Truck Check testing?

Not according to CARB's tester list; plan to bring the truck to the tester. The nearest listed mobile tester is [Full Port Diagnostics](https://ctcfinder.com/tester/full-port-diagnostics-los-angeles/) (about 1 mile).

### Can Oscar Diaz test a 2012 or older diesel truck?

Oscar Diaz does not list smoke opacity testing, which older non-OBD diesel trucks need. The nearest listed tester that does is [Absolute Inspections](https://ctcfinder.com/tester/absolute-inspections-los-angeles/) (about 2 miles). Trucks from 2013 on get an OBD scan instead.

### How much does Oscar Diaz charge for a Clean Truck Check?

Oscar Diaz has not published prices with us; call (330) 409-9181 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 Oscar Diaz a CARB-credentialed tester?

Oscar Diaz 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

- **[Full Port Diagnostics](https://ctcfinder.com/tester/full-port-diagnostics-los-angeles/)** — 11428 Evers Ave, Los Angeles, CA 90059 — (323) 326-0416 — 1 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Absolute Inspections](https://ctcfinder.com/tester/absolute-inspections-los-angeles/)** — 8003 Lou Dillon Avenue, Los Angeles, CA 90001 — (323) 781-8271 — 2 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Imperialsmog](https://ctcfinder.com/tester/imperialsmog-los-angeles/)** — 815 E Manchester Ave, Los Angeles, CA 90001 — (818) 747-5229 — 2 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Jairo Santacruz](https://ctcfinder.com/tester/jairo-santacruz-los-angeles/)** — Los Angeles, CA 90001 — (323) 489-9330 — 2 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[U & A Auto Registration Services LLC](https://ctcfinder.com/tester/u-and-a-auto-registration-services-llc-los-angeles/)** — 648 E Florence Ave, Los Angeles, CA 90001 — (323) 746-8211 — 2 mi. Services: mobile testing, OBD testing.
- **[Cz express llc](https://ctcfinder.com/tester/cz-express-llc-los-angeles/)** — 150 West 66Th Street, Los Angeles, CA 90003 — (323) 697-1433 — 2 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.