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Q: Car lacks power during acceleration onto freeways

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I have replaced spark plugs and wires fuel filter about 4k miles ago maybe less replaced air filter during a oil change from oil can henrys about a month ago but the last few days everytime i floor it i lose power sometimes the car wont go anywhere for a moment if im at a light. No service engine lights are on everything else is normal.

My car has 195000 miles.
My car has an automatic transmission.

A: Hi there, thanks for writing in. If the car...

Hi there, thanks for writing in. If the car was misfiring, there would be a check engine light that is flashing, or at least illuminated while driving. Since there are no lights illuminated on the dash, it is most likely an issue that won't trigger a check engine light. It's hard to say exactly what it might be without being able to look at the car and drive it first hand, but my guess is that you could have a problem with the automatic transmission. Especially since you said sometimes at a stop light when you accelerate, it goes nowhere. There is also a chance it could be low on power due to low compression caused by failing head gaskets, which are extremely common for this generation Subaru motor. The last thing I will suggest would be a failing fuel pump, that isn't delivering enough fuel volume and pressure to the engine.

This is not a complete list of what could be wrong, as there are literally dozens of possibilities, these are just the most likely guesses based on what I now so far. If you want to have the problem professionally diagnosed, I would suggest having a qualified professional, such as one from YourMechanic, diagnose your low power issue.

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