Automotive diagnostic second opinion

Prove what’s broken before buying the part.

Upload the symptom, sound, video, photo, or trouble code. NextTest Auto ranks likely causes and gives you the cheapest useful tests to run next—before the parts cannon empties your wallet.

Start free. No confident guessing disguised as certainty.

NextTest Auto hero
Next useful test$0–$15

Inspect tire wear, then swap front wheels.

The NextTest promise

Evidence over expensive guesses.

Cheapest informative test first

Uncertainty stated clearly

Safety and urgency called out

Diagnosis, not divination

One symptom becomes a testable plan.

Good technicians do not jump from noise to new part. They narrow systems, test failure modes, and confirm the root cause. Your report follows that same sequence.

Evidence quality

78%

More evidence requested

“Record the driver-front wheel while it rotates.” When evidence is thin, NextTest Auto asks for what will improve the diagnosis.

  1. 01

    Submit the evidence

    Add your vehicle, symptoms, photos, video, sound, scan codes, and any repair estimate you want checked.

  2. 02

    Follow the cheapest useful test

    NextTest Auto ranks likely causes, then tells you which low-cost test can eliminate the most possibilities.

    Cheapest test first

    Highest probability first

    Eliminate multiple causes

    Measure before replacing

  3. 03

    Decide with evidence

    See urgency, DIY difficulty, expected costs, confidence, and whether to drive it, fix it, or park it.

    DRIVE ITFIX ITPARK ITDIY PAIN LEVELCOST RANGE

Shopping for a used car?

Turn driveway evidence into negotiating leverage.

Upload the VIN, cold-start sound, dashboard, exhaust video, visible leaks, and scan codes. Get a risk score, likely repair exposure, seller questions, and a buy, negotiate, or walk recommendation.

Marketplace gamble score

63/100

Moderate risk

Estimated near-term repair exposure

$450–$1,300

Pay for the depth you need

A second opinion should cost less than a wrong part.

Begin with a free check, deepen one difficult diagnosis, or size up a Marketplace car before money changes hands.

Basic Check

A quick first pass when you need direction.

Free

  • Basic probable causes
  • Basic risk level
  • Limited diagnostic suggestions
Start a free check

Full Diagnostic

Best starting point

A practical plan for one vehicle problem.

$7.99

  • Probability-ranked causes
  • Cheapest diagnostic sequence
  • Urgency and DIY difficulty
  • Estimated repair costs
Analyze my vehicle

Deep Workflow

For intermittent or harder-to-isolate faults.

$19.99

  • Multiple evidence rounds
  • Detailed testing instructions
  • Expected measurements
  • Repair decision tree
Start troubleshooting

Used-Car Check

Know the gamble before you make an offer.

$29

  • Vehicle risk score
  • Code and visible-problem analysis
  • Expected repair exposure
  • Buy, negotiate, or walk guidance
Check a used car

Before you submit

Straight answers about remote diagnostics.

Diagnosis before parts

Don’t fire the parts cannon yet.

Show us what the car is doing. We’ll help you find the next test worth running—and the guesses worth ignoring.

Start a free vehicle check