OBD II Error message

Thanks Bill, The trip I was taking this afternoon was only a couple miles so the engine probably did not get to operating temperature. I understand that the P0456 code is very common but what is the significance of the "done"?

-billy ray

Thanks for the quick response.

DONE just means the 'puter is done spitting out codes. It could say, NO MORE CODES TO SPIT OUT, but DONE takes less space in the memory.

The codes from P0440 to about P0460 have to do with the evaporative emissions control system. Most codes that come from here have a basis in reality that stems from the gas cap being left off, or at least not all of the way tight or some variaton on the theme.

It would make it simpler for those of us that went to public school decades ago.

We were forced to tune our vehicles "by ear" using simple hand tools (a screwdriver and ignition wrenches) as cars did not have computers.

It also seems to me that for a decade after computers were introduced into cars they ran like $hit because you could no longer make any adjustments without breaking off limiter caps or drilling out the lead plugs blocking the adjustment screws.

Thank you. I have been advised that this error code will reset itself if the problem was caused by a loose gas cap. It did surprise me somewhat that the code explainations don't offer the "check your gas cap" advise.

Here are all of the P0440, Evaporative Emission Control System Codes,

P0440 Evaporative Emission Control System Malfunction P0441 Evaporative Emission Control System Incorrect Purge Flow P0442 Evaporative Emission Control System Leak Detected (small leak) P0443 Evaporative Emission Control System Purge Control Valve Circuit Malfunction P0444 Evaporative Emission Control System Purge Control Valve Circuit Open P0445 Evaporative Emission Control System Purge Control Valve Circuit Shorted P0446 Evaporative Emission Control System Vent Control Circuit Malfunction P0447 Evaporative Emission Control System Vent Control Circuit Open P0448 Evaporative Emission Control System Vent Control Circuit Shorted P0449 Evaporative Emission Control System Vent Valve/Solenoid Circuit Malfunction P0450 Evaporative Emission Control System Pressure Sensor Malfunction P0451 Evaporative Emission Control System Pressure Sensor Range/Performance P0452 Evaporative Emission Control System Pressure Sensor Low Input P0453 Evaporative Emission Control System Pressure Sensor High Input P0454 Evaporative Emission Control System Pressure Sensor Intermittent P0455 Evaporative Emission Control System Leak Detected (gross leak) P0456 EVAP Leak Monitor Small Leak Detected (CHRYSLER)

As you can see, the P0456 code that you got is unique to Chrysler products, my guess is that most vehicles will spit out a P0442 in place of the P0456 that you got. It is worth noting that a loose or missing gas cap can cause a

440, 446 and 455, and can play into a 441, 442, and 456. So, when diagnosing these sorts of things, one has to think about all of the various ways the same thing can expose itself, and the interrelationships of the various components.

As for making the code go away, you can wait. Or, you can go to the auto parts store and they will let you use the OBD II Code Reader for free to reset the codes. I am not sure what codes can be extracted by turning the key on and off while you hold your tongue in the corner of your mouth, but the code readers will get everything that has ever happened since the the beginning of time, or the last time the codes were reset - whichever is sooner -- and are generally available to the store's customers for free. The assumption is that you will bring the code reader back and buy your grandkid's inheretance in repair parts.

I cleared the codes tonight. As of yet there are no codes showing. I did check the cap. The central perforated portion shows some rust tinted discoloring. If the code returns I will know to replace the cap. I did have one person ask if there was a vacuum (whooshing) sound when the cap came off. I don't recall the other day but it did not tonight but I don't know what the effect would be as the temperature was 92 this afternoon, it is 75 now and my garage is underground so it is probably even cooler.

We will see it the code returns.

Thanks to everyone for all their assistance, I really do appreciate it.

The new cap went on this afternoon shortly after the junkyard told me to "drop dead creep" for wanting the lighting elements only out of the shifter.