Location & Hours — Midnight Smog (San Marcos)
Off Hwy 78 at Las Posas • Easy parking • Open late Wednesdays
Midnight Smog is conveniently located at 1285 Stone Dr, Suite 101, San Marcos, CA 92078 — just off the Hwy 78 / Las Posas exit. Walk in any day. We perform quick, accurate STAR Certified test-only smog inspections and transmit results to the DMV.
If you need a smog test, we got you covered.
If you fail a smog test, we got you covered.
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STAR Certified
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Fast in-and-out: Most visits take about 15–20 minutes once testing begins.
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Open late Wednesdays: Perfect for after-work smog checks.
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Test-only honesty: We don’t sell repairs—just an accurate, fair inspection.
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DMV e-cert: We transmit results electronically so you can renew right away.
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Free retest: If you originally tested here and need a retest, we’ve got you.
Coming from nearby on the 78 hwy?
Here are some Driving directions:
From Hwy 78 (Las Posas exit): Exit Las Posas Rd, head south toward W San Marcos Blvd, turn right on Stone Dr; we’re in Suite 101.
From Vista: Take Hwy 78 east, exit Las Posas, head south toward W San Marcos Blvd, turn right on Stone Dr; we’re in Suite 101.
From Carlsbad/Oceanside: 78 east → Las Posas, head south toward W San Marcos Blvd, turn right on Stone Dr; we’re in Suite 101.
From Escondido: 78 west → Las Posas, head south toward W San Marcos Blvd, turn right on Stone Dr; we’re in Suite 101.
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Parking: Customer parking is directly in front of Suite 101.
Accessibility: Ground-level entrance.