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Q: Car losing gas mileage and not much power

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My car has been continually losing gas mileage. It started getting 20+ mpg and now it is only getting 18 mpg. Every week it is getting steadily worse. The engine has no miss. I tried using a can of injector cleaner two weeks ago, but it did not help the problem. My house is 15 miles from town and I started taking back roads so that I could drive slowly to make the gasoline last longer. But that plan hasn't been working either. Another problem is that my car does not have much power; it has been sluggish this summer since it was given to me. Perhaps I should cut off the catalytic converter and run it straight to the exhaust pipe without the converter. Yet, another problem is that the brakes are making noises and they also bind. The transmission shifts in a strange way and 1st gear feels like it is slipping a little. The 2nd gear is quick, hard, and jerks (sometimes it jerks me forward). I recently had a problem with a dead battery and yesterday I found that the cables were loose, so I tightened them. I am hoping to do the repairs myself and would you please tell me on which area I should start?

Hello there, thank you for asking about your 1989 Buick Reatta. Vehicles lose both mileage and power over time - especially after 27 years! The only way to combat this is by keeping up on your maintenance and repairs. A well tuned vehicle will perform better in every way. If the brakes are making noises, the pads are probably worn out and need to be replaced. There’s a good chance the rotors need to be replaced, too. If the transmission is slipping, first check the transmission fluid level (this is done with the engine running and at operating temperature). If the fluid is full, then one of the internal transmission holding devices has failed, and the transmission will either need to be rebuilt or replaced. I know you said you want to do the repairs yourself, but I recommend having a professional look over your entire vehicle and tackle some of these issues. A technician from YourMechanic can come to your home or office to do these repairs and inspect why your gas mileage is decreasing.

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