Clear codes to shut off service engine light

The error codes have to be cleared. Go back to Autozone and ask them to clear the code.

Or, buy the FIXD Sensor and do all this type of thing yourself.

https://www.fixd.com/

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please scan the ECM for codes and post them

Diagnose & make the proper repairs that caused
the malfunction lamp to come on & it will go out

Clear it now & you loose the data to diagnose

Do you have a service engine light on or does the smog station tell you that the monitors are set?
A drive cycle won't clear a service engine light if the reason for it was not fixed. Normally a drive cycle or a 25 or so mile drive will be enough for the PCM to run through its test, and if all is well, clear the monitors.
Now some shop scanners and code readers can clear the monitors. Actron is one of the code readers that I know of that will clear monitors (the newer models. older ones did not). They are about $75 for the basic code reader and may be a worthwhile investment for the do it yourselfer.
Auto Zones also have code readers and if theirs is capable may do it for you. Though if you're in California I have heard they don't do that any longer due to people getting codes cleared just before a smog test without fixing the issue first.

Rent a scanner and do it yourself. If the scanner only delivers codes, you need a chart that tells what the codes mean. Follow the clues to repair the ailing components. The scanner can clear the light when the repairs are complete.

Disconnect the battery for a minuit and turn on the light's to power down any electrical power. Reconnect the battery and that should clear the "servie engine light soon",but if there are any DTC codes, the "Service engine light" will come back on.
On board diagnostic (OBD) was designed on vehicles equipped with electronic fuel injection so you can generally retrieve the codes yourself. No need buying a scanner or running to any parts stores to check the Engine Light. This system is called obd1 and applies to most vehicles made before 1995 for domestics and 1993 on imports.

For GM domestic vehicles made before 1995, the diagnostic connector is located under the dash panel by the driver side. To get the check engine codes to flash in your dash panel, use a jumper wire or a paper clip and connect terminals A and B of the diagnostic connector. Turn your ignition key on with engine off and the codes should start to blink. All codes should start with code 12 which is one long flash followed by 2 short flashes. This code 12 means the diagnostic system is normal and will repeat itself continuously if there are no trouble codes. Otherwise, code 12 will flash 3 times before flashing the fault codes.

the codes can be erased or cleared by disconnecting the battery negative terminal for 1 minute and reconnect. Just make sure to check your service manual in case you have electronic equipment such as radio or clock that needs reprogramming in which battery disconnection is not recommended. Finally after performing repairs on the culprit code, always go for a road test to confirm if the problem is fixed.

Good luck and hope this help, here is a link to the DTC codes. http://www.gmtuners.com/OBD1_DTC.htm

oil change might not have they obd2 tester to shut
the light go to auto parts chain store like autozone
tell shut it up for you for free

The cheap and easy way is to disconnect your battery and turn on your headlights and leave it for a few minutes to reset the ECU. Otherwise you will need a scan tool to do it.

The codes all have to be cleared by using a scanner but if the reason the light was on has not been fixed the light will just come back on. If the problem has been fixed the light will go out on it's own after 25 warmup/cooldown cycles. Autozone will read the codes for you free of charge but they will not clear the codes to shut the light off. You either need to buy a scanner or take it to someone who has one. Good luck

make sure your not getting oil down into the holes where plugs go this can mess with the wires.Is it actually skipping?