Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car does not shift

What you are describing may be a result of a faulty speed sensor, potentially low transmission fluid or a even a faulty transmission control solenoid. As your vehicle travels down the road, the computer analyzes data being sent by vehicle...

Q: I've replaced the power steering pump and bled the system, but I continue to get leakage at top of the reservoir.What causes fluid

Hi there. Usually when the power steering reservoir is leaking, it is due to a seal or gasket being damaged or the cap is not properly installed. Unfortunately, this is usually a situation that will require you to replace the...

Q: Replaced my engine. Does the new one need to be adjusted to the higher elevation?

Check all of the sensors and make sure that they are plugged in all the way. The computer system with the sensors are designed to adjust themselves as elevation changes. This is why all vehicles today have computers in them...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...