My check engine light is on how do I get the codes?

Check the idle air control valve could be sticking and for vacuum leak

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Please run down this guide and report back.

You need to find out what code is stored, then repair it to get the light out, or you can take a gamble that nothing will happen. If you find out the code we can help.

Cross these two terminals as shown, then turn the key on. Count the flashes, a 22 will flash as 2 flashes then a short pause, then 2 flashes, if more than one code is stored, the pause will be longer. The codes will display three times and end with 12. Write them down and post here. This connector is right under the middle of the dash...Start with this...post result.

Good morning,

This sounds like a bad ECM but needs to be confirmed.

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

https://www.2carpros.com/articles/engine-stalls

Can you check the codes for me and see what codes are set? I attached the procedure below for you to pull the codes.

The ECM incorporates a diagnostic program which, when activated, will flash codes stored in the trouble code memory through the "check engine" lamp. A diagnostic connector, located under the instrument panel, is used to activate the self-diagnosis system. The connector, allows access to system circuits and contains a test terminal which, when grounded with the ignition on and engine stopped, causes stored trouble codes to be flashed on the "check engine" lamp.

When the diagnostic terminal is grounded (jumper terminal "A" to "B") with the ignition on and engine stopped, codes are displayed in numerical order, always starting with Code 12 which indicates that the self-diagnosis system is operating properly. Trouble codes, are displayed in the following manner: Code 12 is displayed by one flash, a short pause, then two flashes and a longer pause. Code 12 will be displayed 3 times in this manner, then any additional codes stored will be displayed 3 times each in a similar manner until all codes have been displayed. Once all codes have been displayed. The process will be repeated as long as the test terminal remains grounded. Do not ground the diagnostic terminal until the ignition is "on" and engine is "off" (not running). After trouble codes have been noted, the ground wire should be removed from the test lead and the engine should be started. When the engine is started and there are no other codes except Code 12, the "check engine" light should go out after approximately 5.0 seconds, indicating that the ECM has not detected a malfunction. However, if the ECM detects a current malfunction, the "check engine" lamp will remain illuminated while the engine is running. A trouble code indicates a possible system malfunction. If a trouble code can be obtained, even if the "check engine" lamp is "off" when the engine is running, a "system performance check" should be performed and the indicated circuit should be inspected.

Use the appropriate diagnostic charts if trouble codes can be obtained with the "check engine" lamp "off." A System Performance Check and a thorough physical inspection of the circuit involved should be carried out if any of these codes are evident. Repair as necessary.

Removing battery voltage to ECM terminal "R" for a period of 10 seconds will clear all stored trouble codes. This usually can be accomplished by removing the ECM fuse, if equipped, from the fuse block. In some cases it may be easier to disconnect the negative battery terminal. However, doing so will result in deprogrammed ETR radios, electronic clocks and Trip Computers.

If the problem was fixed, the light should not have come back on, maybe another problem. Your obd1, check your own codes. You can take negative battery cable loose for several seconds, to erase. If the problem isn't fixed or a different problem, the light will come back.

Here is how you get the codes:

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

and

Flash codes are better than nothing. Use a jumper wire between terminals A and B, turn key on, no crank, check engine lite starts flashing, you count the flashes to get the codes.

Hi there,

This is indicating that there is a set fault code in the ECU. Get a scan done to identify this code.

Mark (mhpautos)

HI there,

The ECU is a processing unit, it gathers information from sensors and sends commands to engine and transmission control units, when a fault is detected it stores specific fault codes for that unit. The check light is a visual indication that there is a fault code in the system, so when you get a scan, you will get a fault code that will identify which control unit is acing up.

Mark (mhpautos)

Check for applicable trouble codes. I don't believe you have an oil life monitor on this vehicle? You can check for trouble codes, yourself. You use a jumper wire between the A & B terminals at the datalink connector. Turn key just till the dash lites come on, no further. Then the lamp on the dash starts flashing, you count the flashes to get the trouble codes. Your looking for two digit codes. Let us know the code numbers, if you find any?

If the check engine light is coming on, that means there will be a trouble code stored in the computer which will identify where the problem is coming from. Have the computer scanned to get the codes. Most parts stores will do it for free.