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Q: Reduced power loss

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I had to get a boost after my car sat for 6 months now I am getting a power loss light an air bag light and a power steering lights coming on its running very rough and when I shut the car off it continues to run for a few seconds

My car has 120700 miles.
My car has an automatic transmission.

A: There are a few things you can do, but a sc...

There are a few things you can do, but a scan tool will be required at some point. Newer cars have a lot of electrical demands. When you jump start a car that has a dead battery, the battery has to charged by the alternator. It is not designed to have that kind of load on top of providing power for everything else.

Your car has electric power steering by the way. The power steering light, and the air bag light, are most likely the result of too high, or too low, system voltage. This should be verified by checking for stored trouble codes.

What you can do is to have the battery charged and tested. A good battery can take 8 hours to charge at 15 amps. Much longer on a trickle charger. The power loss light is the computer telling you that it will give you limited engine throttle. This could be a problem with the electric throttle motor or sensors, or it could be another problem, like a misfire. The computer will reduce power output when it detects a misfire to prevent damage to the catalytic converter.

The engine could have a misfire for many reasons. It could be a problem with the ignition system, such as a spark plug or ignition coil. You may have a fuel quality issue due to it sitting for an extended amount of time such as fuel separation, or water in the fuel.

What you can do is top off the tank with fresh gasoline. I would suggest with this host of problems is to have all of the systems scanned for trouble codes. Each one will need to be diagnosed individually. Once the cause of the lights is determined, and repaired, then the codes can be erased and the systems checked for proper operation. If you need help in doing so, consider the assistance of qualified technician who can diagnose the trouble codes and fix your vehicle at your home or office.

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