1 Answer

This problem can be caused by several issues, including low quality or altered fuel or even a loosely tighten fuel cap, the most common cause is a dirty MAF flow meter sensor.

The MAF sensor (Mass Air Flow Meter Sensor) is in charge of detecting how much air (in mass, not volume) is coming in to the engine, so the ecm computer can calculate the amount of fuel to be injected.

Some times this sensor gets contaminated by lots of microscopic debris that scape the air filter and accumulate on its sensing parts over time. The resulting effect is that the MAF flow meter sensor gets less “sensible” and detects less air than it is currently entering the engine. The reaction of the ecm computer will be to inject less fuel to keep the air fuel balance, taking as reference the false reading of the MAF flow meter sensor. This will produce a too-lean mixture, which is responsible of the hesitation, the loss in power and the check engine light. 

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