Here's how MECH AI thinks.
Follow one real check-engine light — a 2014 Camry throwing P0420 — from the symptom all the way to a $42 part and ~$1,200 saved. No jargon, no forum threads, no guessing.
Tell it what's wrong.
Start the way you'd talk to a mechanic friend. Describe the symptom in plain English — "rough idle, smells like gas" — or paste a trouble code (a DTC) you saw on any reader. Both work. No login wall to start.
- Plain-English symptoms, a photo of the dash, or a pasted code
- Built-in OBD-II decoder turns cryptic codes into a starting point
No login wall, no $150 diagnostic just to ask the first question.
Grounded, not guessed. It weighs your exact engine (2AR-FE), the code, and known patterns — not a generic forum answer.
It reasons about your exact car.
Generic chatbots say "replace the catalytic converter." On a 2014 Camry's 2.5L, P0420 is far more often a tired downstream oxygen sensor — a $45 part, not a $600 one. MECH AI ranks the likely causes for your specific engine and tells you the cheap one to rule out first.
It tells you the cheap likely cause before the expensive one.
Try this on your own carThen it shows you exactly how — and what to buy.
Step-by-step repair guides, the relevant TSB in plain English, and the exact part number with Amazon and eBay links that fit your year and trim. Not "an O2 sensor" — the Denso 234-4209 that bolts onto your Camry.
- Torque specs, tools, and difficulty so you know what you're in for
- MECH Vision can estimate a repair from a photo
And when it genuinely needs a lift or a press, it says so: take it to a shop.
Denso 234-4209 O2 Sensor
$42.87 · Direct fit · ~45 min
The math, made literal.
Same P0420. Two very different afternoons.
With MECH AI
$42
Denso O2 sensor + your afternoon
Dealer quote
$1,200
Catalytic converter you didn't need
A shop diagnostic alone runs $120–$200. MECH AI is free to start — no card required.
"We bounced ideas back and forth — it helped me diagnose and confirm with utmost accuracy what was causing it."
Know what's wrong. Know what to do. Know what to buy.
Try it free on your own car. No card, no catch — upgrade when it's already saved you a shop visit.
100K+ downloads · no card required