Why is Check Engine on? 5 most common causes

1. Loose or damaged gas cap

The most common cause. Tighten the cap and drive a few dozen km.

2. Failed oxygen sensor

Can increase fuel consumption by up to 40%.

3. Damaged catalytic converter

Driving with a bad catalytic converter is dangerous!

4. MAF sensor failure

Often cleaning is enough.

5. Worn spark plugs

Replace every 30-60k km.

Professional diagnostics from 150 PLN. Mobile service in Wrocław.

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▸ ⚖️ Legal information about pricing and services

All prices listed on this website are approximate and may vary depending on the make, model, year of your vehicle and scope of work. We make every effort to keep information accurate and up-to-date, however minor discrepancies may occur due to market conditions and cannot serve as grounds for claims.

If in doubt, please contact us directly for an exact quote.

Information presented on this website does not constitute an offer under Article 66 §1 of the Polish Civil Code, but an invitation to negotiate under Article 71.

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