Q: Rough idle and sputtering off and on

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I've had my car for almost a year now. Once in a while I will start it up and out of nowhere it has an extremely rough idle. I can hear a thump-tump... thump-thump... in the engine. The whole car bounces when the thumps and when it's standing in neutral the shift stick is shaking a lot. It stalls often in a low gear moving slowly (parking etc.), the engine is loud, it accelerates very slowly and barely gets up hills. Every time I'm about to take it to the mechanic I will start it up again and it's gone all of a sudden and the car is fine again. Sometimes after it's been sitting overnight, sometimes literally just after it's been sitting for 20min. I have new spark plugs and have had regular oil changes. Thank you for you time.

My car has 200000 miles.
My car has a manual transmission.

Hello, and thank you for writing in. Considering the age and mileage of the vehicle, there could be a number of issues going on. At this point in its life, there are going to be critical components that will need to be replaced, all depending on how the vehicle has been taken care of up until this point. You want to look into the fuel, air, and spark systems. With new spark plugs, consider replacing the fuel filter, and possibly the pump. If it is the original pump, it has worked hard and is likely weak. Also make sure you air filter is new. If the problem continues, consider having your vehicle scanned for diagnostic codes. Even without an engine light, there may be codes that have been recorded by the computer which can shed some light on the situation. For more diagnostic help, contact our service department to schedule an appointment.

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