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Q: idles rough after heavy acceleration, going up hill, getting off freeway, weak warm start ups

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My car idles rough after heavy acceleration, going up a hill or getting off the freeway. It runs normal after a few minutes of slow easy driving and accelerating is smooth. Also my warm start ups are weak. When the car starts up cold there is not problem but after the car is warm it hesitates when starting up.

A: The most common cause of this is either a c...

The most common cause of this is either a charging system issue, such as the alternator or battery, or low fuel pressure from a clogged line or failing fuel pump. Either the charging system or the fuel system can have low output once the vehicle warms up and is under heavy demand. They may seem to work under normal condition, but once anything more demanding is required, the faults become visible. To have this checked, a qualified mechanic from YourMechanic will have little trouble diagnosing your acceleration issue and performing any repairs required.

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