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Q: Flickering lights

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The dash lights flicker as do the headlights. The car runs a little rough it has not been tuned could this be the problem?

My car has 210000 miles.
My car has an automatic transmission.

A: If the idle fluctuates enough, you might s...

If the idle fluctuates enough, you might see some flicker, because the engine of course drives the alternator. However, the roughness could be a separate issue - that is, the alternator could be failing, too. One diagnostic strategy is to look at the charging system first. If the charging system is working (and the battery passes a standard load test), resolve the poor running condition and that might resolve the flickering lights. As far as the rough running, due to the high mileage, before all else I would test the engine cylinder compression to see what the basic mechanical condition of the engine is. From there (if it passes) there are innumerable ignition and fuel system faults that could be the cause. A YourMechanic certified technician can come to your location to perform a general lights inspection, or a Car idle is rough inspection, in order to diagnose these issues.

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