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Q: My car doesnt want to run correctly when the AC is on.

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Bought the car 3 days ago. It was kind of shaky so we did a tune up. I put in the Autolite platinum spark plugs, new oil and filter, and lucas stop leak and stop slip transmission oil because it was very low. After all that the car didn't even want to drive. So we reset the computer by removing the battery and later turned it on. we got it out into the driveway and the car didn't want to accelerate. It stayed stuck it doesn't even automatically shift. It won't pass 30mph. My gas went down half a tank by testing it out around the block. So we stopped driving it. the next day I put my windows down and backed up and starting driving with the ac off and i stepped on the gas slowly and it started shifting again on its own. But it still feels a little forced but not like before. When the AC is on it is even worse. But with the AC on or off it still won't accelerate normally. I have to accelerate slowly and let it catch speed. I have no idea what the problem is.

My car has 101700 miles.
My car has an automatic transmission.

Hello, thanks for writing in. From the symptoms you describe it would appear that your vehicle is experiencing some sort of engine or transmission related problems. If the vehicle will not drive over 30 mph then it may be possible that vehicle is in limp mode. Limp mode is activated when the computer detects a serious issue with the engine performance system or the transmission. It will significantly reduce vehicle power and performance, in order to reduce the possibility of damage occurring to the vehicle. From what you describe it would appear that the vehicle is experiencing more than one issue, and the issues are greatly affecting the drive ability of the vehicle. For this reason I would recommend having a professional technician look at the vehicle for the most conclusive diagnosis.

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