My service engine soon light is on on my 2004 Mitsubishi Lancer.

.039--.043 in gap

To reset the computer, disconnect the battery for a couple minutes, then hook it back up again. This will not solve the problem if there is one. The check engine light comes on to let you know that there is a problem. If you take it to an auto parts store, they can read the trouble codes and reset the check engine light.

You must take your car to any local auto parts store and have them put a scanner on the car so it could give them the right code to pin point the problem.

just because the engine light is on dont mean there is a thing wrong with you car some auto car manufactures will use a timer module to tell you that your car is in need of a check up. but just to make sure there are no problems you can take your car to any auto parts store and they will scan it for free and tell you if the computer has any stored codes that may or may not be a issue. in your owners manual there should be instructions on how to reset the time that the service engine soon light will come on.

The check engine light/service engine soon (yellow light) comes only when the computer control unit (called the PCM) senses a fault in the electronic controls of the engine and/or the emission system u will seldom feel the car engine run any different, there are about 200 possible faults that turn the light on, to know what has developed a problem you must have the system tested, this is called an OBD2 fault code test, Kragen and Autozone parts stores do this testing for free.

reset the ECU. Remove the battery lead (black, negative one) for 30 minutes. Refit, clean up the terminal while you are at it with emery paper and fire up the car. Let it idle for 10 mins.

This resets the ECU and the service light will go out.

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most salvo auto parts stores will test your codes for free they can only offer parts not service. but its the only company that does it for free

easiest thing to do is go to advanced auto parts or auto zone and get a free diagnostic test, they will tell you what it is

This could be caused by a low fuel pressure or poor plugs/wires. Do a fuel pressure test, if low replace filter, if still low replace pump. Also replace spark plugs and wires if you have not done so. If check engine light is on you can bring vehicle to local parts store to have them retrive trouble code. Thanks

you have to see if the coil pack fire up do you have spark coming out of the coil pack cylinder 2 never mind the other code the missing cylinder make the other sensor malfonction check if you have spark coming out of the coil pack if not change the coil pack if you have you spark check the compression let me know pierre please dont rate right away we work together to fix our problem because i whant you to get our car running good and i whant a fixya anything else is bad for me thanks pierre