My check engine light came on tonight.[:@] I understand that this could be because my gas cap is not on tightly, I just got gas yesterday so this is a possibility. My husband took my gas cap off and replaced it tight and the light did not go off. Does this rule out the gas cap problem? My husband also cycled the key 3 times and there was no code, not sure if we did this correctly so can you please explain how to do this and where the code will show up. [&:]

 

first of all what year vehicle do you have, if it is 95 or later you have what is called the obd1 system, if it is 96 or newer you have obd2 . if you vehicle is obd1 then you will turn the key on and off 3 times and after the third time with the key still in the on position, you will look for a check engine light by you speedometer you will then count the flashes as the computer cycles through its test. there will be a short pause between the flashes.

 

I have a 2004, how would I do the test on this one?

 

since your vehicle is a 2004 this is a obd2 system which requires a computer to check the codes. there are a few things that come to mind right away first thing is a bad gas cap, second is a bad o2 sensor and third is a egr problem. since your check engine light has come on you can usually go to a advance auto parts store and they can pull the codes for free. i hope this helps

 

Awesome. We have a 4 hour drive Thursday and I really dont want to drive it not knowing if it is a huge problem or something simple. Thank you so much.

 

just want to see if you got the last email i sent you,

 

Yes I did my husband just wants me to take it to a Auto Zone and have it check tomorrow. It does still have a warranty on it, but we are the second owner so I am not sure if we have to pay to have it transferred over or not.

 

OBD II vehicles do not turn the MIL off immediately after hte problem is repaired. The codeseither have to be cleared witha scanner or by disconnecting the battery for a few minutes. Otherwise, it takes multipledrive cycles for the computer to decide the problem no longer exists.

Have it scanned so you can verify that it even was an evap leak DTC. There are hundreds of MIL-illuminating DTC's, most of which will not immediately and noticeablyaffect driveability