Diagnostic codes for 1999 S10
 

My father-in-law gave me his old 1999 Chevrolet S10 (250k). I love it and want to learn more about working on trucks. The service engine light is on. I used my friend's "U-scan" and found out the truck is returning a code of P0440.

My question is this - they claim it will pull Chevrolet specific codes, but I want to know if it's true, or if there is some other kind of code it may not pull that I'm missing?

Thoughts? Feedback? I want to make sure I'm getting all the codes.

po440 is an evap code. could be as simple as the gas cap not on properly. remove the cap, put it back on and shut off the code and see what happens. could also be a purge solenoid or plugged up charcoal filter, or hose problems associated with those things. if all else fails, you may need a smoke test on your evap system. hope this helps.

Thanks for the reply. i'm aware P0440 means and how to go about fixing it. My question is around readers and manufacturer specific diagnosis codes.