Q: Bad idle with no check engine light on

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I was moving my sister's stuff after she passed away, and all of a sudden my van had a rough idle. I have changed the plugs, wires, fuel injectors, fuel filter and cap and rotor, and I still have a rough idle. I was told to use this stuff called Restore, you add it to your oil, I did but if I go too far with it it stalls out, but starts right back up with No problem. Do you think it could be the ignition coil? Please let me know Lorraine

My car has 177000 miles.
My car has an automatic transmission.

Greetings, I’m sorry to hear about your sister. A rough idle may be caused by many different things such as low fuel pressure, low voltage to the fuel injectors, dirty fuel injectors, a vacuum leak, a faulty Oxygen sensor or a dirty or failing idle air control valve. Any of these possibilities relate to fuel delivery issues that will disrupt the normally balanced air/fuel mixture that would otherwise allow the motor to run smoothly. It sounds like in your case you have touched on all of the ignition related components. Try checking some of the above items that can impact the fuel delivery to see if this doesn’t solve your idling issue. I would recommend having an expert from YourMechanic cometo your location to diagnose your rough idle problem.

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