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.

thanks will do!

This is a new engine in my truck and I would like to know how I can turn the check engine light off. Is there something I can do. I just dont have the time to drop it back off at a shop to have it checked. The new engine is 1 year old. Running great so I know there is not a mechanical issue.
Thank you for any sugestions.
Rhonda

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.

well i noticed acceration while driving was tough, until i got up 30 mph....then everytime i would stop at a light it would idle rough and die on me.. it.did this abit then all off a sudden my truck didnt wanna start it was turning over but didnt wanna start..then i had it towed, went back to my truck the next day and it started right up!? but i let it idle for like 5 minutes then its died..whats going on?

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.

My short wheelbase truck keeps shutting off (losing power) as soon as the check engine light comes on. Any ideas as to why it keeps doing it?

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.

My service engine soon light was coming on and off and I needed a inspection. So I took it to a shop they ran the test one code showed up they replaced the EGR valve and fixed a vacuum leak and it passed. But, I do not remember them resetting the codes! My question is, do you have to reset the codes for the light to not come back on if the problem is fixed? Because mine did.

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.

Thanks, I love this site. :)

Hi! The check engine light comes on only when on the highway and in overdrive, overdrive works fine, no noticeable problem. Any ideas? It doesnt always come on, but lately more often than not.

Thanks in advance for ideas!!

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)

Thanks! If this is the case then is this just a CPU related problem or is it indicating a possible problem with the transmission?

Thanks again for your very quick answer. I will recommend this site to friends!

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)

Excellent, thanks a lot! I will check it out! I advanced the timing from about 26 total advance to 38 the truck runs way better, it idled and was a dog at 28. At idle it was almost 8 degrees retarded, now it runs best at around 38. I live at 2500 elevation so 38 seems optimal, but maybe the CPU does not like the advance in overdrive on the highway now.

How do I reset service engine soon light. The oil and filter have just been changed so it dose not need service and i have been told there is a procedure were you do something with key and mashing accelator pedle a few time and this will reset light???

thanks
REH

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?

after driving on the highway for about 20 min the check engine light comes on and its hard to press the gas sometimes it dont want to get above 40mph

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.

how to get the codes can you help me please?

It will look like this: Jumper A to B and read of the flashes-X....XX is equal to DTC 12

Hello, I'm Danny.

Here is the information you requested. This is a tutorial showing how to retrieve OBD1 codes for a Chevrolet:

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

After performing this get back to us with any code number information and we can then properly diagnose the issues and provide reference materials. Hope this helps and thanks for using 2CarPros.