DavidinKS

I keep getting a check engine light and the code is PCM P0440 (which has something to do with emissions I'm told). Can anybody give me some advice on what's causing the problem?

I've heard it's caused by a sensored that can be tripped when your gas cap is not on tight - I've checked that and it's always tightened down good (several clicks around).


The car is a 2000 coupe m6 stock aside from a blackwing. On a side note what does the reset button do on the blackwing (I bought the car with the blackwing so I don't know much about it)?




Thanks guys!!!

HummelS

If it is (or was) the gas cap, which is usually the cause for P0440, it will require 40 ignition cycles to reset. Try clearing the code and see if it comes back, would be my suggestion.

Edit - the button on the Blackwing will show when it's time to clean it.

DavidinKS

So besides the gas cap; what other things can cause the P0440 code to come up?

kp@hp

P0440 sets when the PCM detects a small leak in EVAP system, most likely a loose or not properly sealing gas cap. To test the system we inject smoke into the evap system, that includes both fuel tanks, vapor canister, purge and vent switches, and all the hoses that connect the system together and look for the leaking smoke. Approx 75% of the time its just the gas cap,
but when its not it can be kinda tricky to track down.
good luck.
kevin
www.hpperformancecorvettes.com