Q: Will bad engine coils cause the car to not want to accelerate?

asked by on February 22, 2017

I have a 2005 Ford Five Hundred. As of yesterday when I attempt to drive my car, I am only able to reach a speed of about 30 mph. If I try going any faster than that the rpm goes up but I can't get any more speed. I had a family member check the engine codes and they told me it was two faulty engine coils.

My car has 200000 miles.
My car has an automatic transmission.

Faulty ignition coils can certainly reduce engine power. Ignition coils provide electricity (anywhere from 25 to 50,000 volts) to the spark plugs. That spark ignites the fuel mixture, which forces the pistons down and creating horsepower. With two faulty coils, your 6 cylinder engine is now essentially a 4 cylinder engine because two cylinders are not providing power. If two coils are bad, you may want to consider replacing all 6 at the same time. If two failed together, odds are the others will not be far behind, especially if they are the same age.

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