
Engine Diagnostics & Repair
We test systems before recommending replacement, so you only pay for repairs your car actually needs — from tracking down leaks to confirming a failing component.
Honest auto repair on 3rd Street
T-21 is the Bayview garage San Francisco trusts — a 5-star Google rating across 140 reviews for careful diagnosis, fair pricing, and work done right.

Services

We test systems before recommending replacement, so you only pay for repairs your car actually needs — from tracking down leaks to confirming a failing component.

Oil service, filters, and general maintenance that keep your car — even an older one — running smooth for the long haul.

Radiator replacement and radiator hose service to keep your engine running at the right temperature.

Catalytic converter and oxygen sensor service — tested first, replaced only when it's truly needed.

Spark plugs, ignition switch repair, and tune-up work to keep your engine starting and running strong.

Alignment and wheel balancing for a smoother, safer ride and longer-lasting tires.
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We don't throw parts at problems — we fix them.
Our story
At T-21 Auto Services and Repairs, we believe you should only pay for the work your car actually needs. That's why we test before we replace — customers know us as the shop that doesn't just throw parts at a problem, whether we're tracking down a leak or confirming a catalytic converter really is at the end of its life. From our garage at 4049 3rd Street in San Francisco's Bayview, Joe and the team handle everything from oil service and spark plugs to radiators, alignments, and emissions work — and we're known for keeping older cars running smooth for years. Fair pricing, straight answers, and repairs that hold up: that's what has earned us a 5-star rating across 140 Google reviews. We're open six days a week and happy to take walk-ins. Stop by or give us a call — we'll give you an honest assessment and get you back on the road.
What customers say
“What I especially appreciate is that they don't just throw parts at a problem. They tested the catalytic converter system before recommending replacement, caught related issues while already working on the car, and handled smaller maintenance items like filters in a very fair way. That kind of judgment matters a lot when you're maintaining an older vehicle.”
“I finally found a shop that has honest mechanics who work there. Joe and his Staff is very knowledgeable and helpful. Their prices are affordable to all budgets.”
“They always do great work. Job is always fair with pricing and their work is reliable and fast. For as old as my car is they keep it running smooth. If you're ever in need these are the guys to go to.”
Serving San Francisco, CA.
4049 3rd St, San Francisco, CA 94124, USA
4049 3rd St, San Francisco, CA 94124, USA
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