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Q: Is my transmission going in my car?

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Everytime i start my car it revs itself up to 4rpm and holds for a moment then drops down to 1- 1 1\2. As soon as i put my car in drive it will either "chug" and not allow me to accelerate or as soon as i press on the gas my car will go and basically drive itself(same in reverse only with othe the chugging). When i do drive my car bounces between 1 1/2 and 2 rpms. There are also points were my breaks are great or almost dont work. I have just replaced the o2 and speed sensors and the thermostat almong with unplugging the battery.

My car has 170000 miles.
My car has an automatic transmission.

A: You need to have the computer tested for co...

You need to have the computer tested for codes and the engine checked for a vacuum leak to the brake booster. This would account for the high idle and lack of brake power assist. The most likely cause is that the brake booster hose came out when you were working on the engine to replace the O2 sensor. A certified mechanic could help you diagnose your acceleration issue and the other symptoms you are describing to find the right fix.

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