Fuel Supply & Injection - Fuel, Air & Emission Symptoms

Common symptoms and diagnostic guides.

Sometimes idle feels unstable cold idle

An unstable or rough idle when the engine is cold often stems from air-fuel imbalance, sensor errors, or ignition issues and typically stabilizes once the engine warms up.

medium risk

Air weak in miles long traffic

Persistent weak engine performance or loss of power in long traffic (stop?and?go) often stems from airflow, fuel, or ignition control issues that affect idle stability and acceleration.

medium risk