PulsecarPulsecar

Check engine light on — what does it mean and what to do?

The amber check engine light comes on when the engine control unit detects a fault in the ignition, fuel, intake or exhaust system. The light itself doesn’t tell you what’s broken — reading the fault codes and diagnostics do. What matters is whether the light is steady or flashing.

Book a diagnosis +48 571 058 591

Most common variants and causes

Steady, the car drives normally

Check within a few days
  • A sensor (lambda, MAF, temperature)
  • Intake or EVAP leak
  • EGR valve, DPF filter

The fault can get worse and more expensive. Drive carefully and book a diagnosis.

First step: Computer diagnostics — from 100 złAuto electrician →Book a diagnosis →

Blinking, the engine runs rough

Avoid driving — call us
  • Misfire: coil, spark plug, lead
  • Injector
  • Unburnt fuel can damage the catalytic converter

Driving on may be unsafe or cause serious damage. Call us — we’ll advise whether to drive in or use a tow truck.

First step: Computer diagnostics — from 100 złAuto electrician →Book a diagnosis →

Lost power (limp mode)

Check within a few days
  • Boost pressure (turbo, leaking hose, valve)
  • Clogged DPF or EGR valve
  • Sensor or throttle body

The fault can get worse and more expensive. Drive carefully and book a diagnosis.

First step: Computer diagnostics — from 100 złAuto electrician →Book a diagnosis →

What you can check yourself

  1. Check whether the light is steady or flashing — flashing means misfires and needs a quick response.
  2. Notice whether the car has full power and idles smoothly.
  3. After refuelling, check that the fuel cap is properly closed.
  4. Don’t clear the fault codes before your visit — it makes finding the cause harder.

How we check it in the workshop

We read fault codes from all control units, check live engine data and, if needed, take a test drive. We discuss the results and give you a repair quote before any work starts.

This is guidance only, not a diagnosis. We’ll find the exact cause at our workshop in Bielany — you approve the quote before any work starts.

Frequently asked questions

Can I drive with the check engine light on?

If it’s steady and the car drives normally, you can get to the workshop, but don’t put off diagnostics. If it’s flashing or the car loses power, limit driving and give us a call.

How much does computer diagnostics cost?

With us, from 100 PLN. After diagnostics you get a repair quote to approve.

Does clearing the fault code fix the problem?

No. The light will go out, but if the cause remains, the fault will come back — often within a few kilometres.

Other symptoms

Knocking over bumpsCar pulls / steering off-centreBrake problemA/C not cooling or smellsCar won’t startRattling from the engineExhaust smoke / loss of powerJerky gearbox or clutchEngine is overheatingPuddle under the car / leakCar jerks when accelerating
Not sure? Take the symptom test (2 clicks)