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Smoke on startup

Brief puff of smoke on startup; can be valve seals, turbo, PCV, or condensation.

MEDIUM RISK

Common symptoms

  • See page for quick checks

Cost expectations

Typical costs vary by car and region. Use this as a ballpark.

  • DIY / parts: £20–£80
  • Garage / labour: £80–£250

Most likely causes (ranked)

Start at the top. Rule out the common, cheap causes before expensive ones.

  1. Condensation (white steam)
  2. Valve stem seals (blue puff)
  3. PCV system pulling oil
  4. Turbo oil seals
  5. Overfueling on cold start

Quick checks (fast, low-cost)

Fast checks you can do with basic tools before buying parts.

  • Identify smoke colour and duration.
  • Check oil consumption trend.
  • Inspect PCV and breather hoses.
  • Scan cold-start fueling trims.
  • If coolant loss exists, test for head gasket.

Recommended tools

These tools make diagnosis faster and stop you buying random parts.

Related fixes

If your symptoms don’t match perfectly, check these next.

What to do next

  • If it’s only condensation, it disappears when warm.
  • Blue smoke + oil use: investigate PCV/valve seals/turbo.