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Q: Engine light won't go off

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I've replaced a coil pack, both O2 sensors, both solenoids to canister, spark plugs, wires, gas cap, air filter & a faulty throttle connector on top of the engine. Have disconnected battery & manually cleared w/ scanner. I drive less than 50 miles and light comes back on! Have done this three times. What else do I need to look at? How many times does the memory store the codes?

My car has 159399 miles.
My car has an automatic transmission.

Some of the items you have replaced are maintenance items, so that is good. Your car utilizes OBD-II which is a diagnostic system that outputs "diagnostic trouble codes" if a malfunction is detected and, at the same, alerts the operator that these codes have been stored by illuminating the Check Engine Light (CEL). If the CEL is still on, the best thing to do is download the remaining codes and see what they point toward. Usually, a code will be accompanied by a basic statement of the "fault", but all of the devices, sensors, components, wiring, grounds, and even stuff not directly related (or mentioned) in the code, will have to be individually tested to accurately find the problem. So, at this stage, what I would recommend is have a certified Mechanic perform a check engine light diagnostic. The Mechanic will have to look at the many possibilities that arise from the code(s) that are downloaded but at the end of that effort you will finally get an identification of the root issue that is still setting the CEL. Once you have that root issue, the Mechanic will be in a position to explain the repair strategy and what, if any, parts will be required to fix your car.

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