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Q: Car chugs when warms up at accerleration

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Hi my car starts and runs great until it warms up.! Then when I go to accelerate it chugs and Jenks and I hear a rattling noise. It does that until I reach about 45 mom and then it runs just fine. I am thinking it is a bad cat. Do you think this might be the issue? I have replaced all of the sensors, done a oil change and a tune up and changed all the coils also. Thank you.

My car has 250000 miles.
My car has an automatic transmission.

Hi there:

Usually the symptoms you’re describing are more related to a vacuum leak, worn out spark plugs, bad spark plug wires or issue with the ignition system. It’s also possible that dirty air and fuel filters, mass air flow sensor and EGR valves may need to be replaced. There are multiple parts on the vehicle that control it’s acceleration and efficient operation of the engine, which is why it might be best for you to have a professional mobile mechanic complete an engine is shaking, vibrating and pulsating inspection; so they can determine what needs service on your Impala to resolve this issue.

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