i have a 97 dakota with a 3.9 5 speed 4x4. the check engine light came on today. the motor still runs right. the 2nd oxygen sensor was replaced a couple of months ago. could it be the first o2 sensor? i know the cat can be clogged up because its hollowed out. everything still runs right and works fine? any suggestions on what it could be?

 

With a check engine light, there are several possibilities. The easy way to find out is run the diagnostic codes and check the numbers against the service manual. If you don't know how, with mopar products all you have to do to check the codes is turn your ignition switch on and off three times in a row WITHOUT starting the vehicle and LEAVE the ignition in the on position the third time. Then watch your check engine light and it will flash the trouble code numbers. Reference numbers to manual code diag page and it will tell you what is wrong. Note it may tell you several different things are wrong, but this could also be due to one primary problem that makes the computer think that other parts are not working correctly because they are trying to comensate for what is wrong. (i.e. intake air sensor could be bad, but it will also say O2 sensor bad because of air mixture starting at intake.)

 

the code that popped up was #12. whats that mean

 

Is 12 the only number it flashed? 12 is a common number that usually does not turn on the engine light. All it says is that the battery has been disconnected within the last 50 turns of the key. Have you disconnected battery lately? If you did, has the CEL came on since doing so?

 

yes 12 is all it said. i read on a wecsite somewhere that it was a emissions control valve or something so i d/c the battery and it went off. and no it had no been s/c the last 50 turns or the key. the light hasnt been on since

 

I don't know what website you found that info on, but 12 on chrysler products is always a disconnected bat within the last 50 turns of key. You might of had a loose bat connection and when you reset cp by disconnecting and reconnecting bat it tightened it up, or it could have been a bad contact i.e. corroded terminal. Glad you got it fixed though.

 

where can i find a list of codes?