Code PO 440 keeps coming back...
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,170
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From: Magnolia Greens NC
Code PO 440 keeps coming back...
..my OBD says it is an "EVAP Emissions Malfunction".. I have: 1.Replaced gas cap..3times 2.Replaced EVAP Solenoid(GM part) 3.Replaced PCV...4. Erased this 440 code several times but it keeps coming back via Check Engine signal...and yes, I have Kooks long tube headers,hi-flo cats but with 02 "Simulators"... my performance team believes a "Smoke Test" is the last resort to locate this fuel-tank-related tiny air leak ... ANY OTHER THOUGHTS OR CURES OUT THERE???
Drifting
Joined: Oct 2003
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From: bloomfield nj
your fault is for a large evap leak.there is a green cap on the left side of the motor in line with the purge valve.this is the evap test port.make sure that cap is tight.also are you sure you have a non-vented gas cap.
Race Director
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From: Redsox, Pats, Celts & Bruins !!! Redsox Nation !!!
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Originally Posted by dpd
your fault is for a large evap leak.there is a green cap on the left side of the motor in line with the purge valve.this is the evap test port.make sure that cap is tight.also are you sure you have a non-vented gas cap.
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,170
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From: Magnolia Greens NC
BINGO!!...located the Evap Test Port Cap (mine's Black,not green) and it was NOT TIGHT...turned it full turn & 1/2...now, it is dang tight!...the new gas cap is the NON-vented type....so, I think you great minds have given me hope . The "Check Engine" light, IS NOT a pretty light, THANKS, Bill
Pro
Joined: Jun 2003
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From: Castle Rock Co
Originally Posted by trussme
BINGO!!...located the Evap Test Port Cap (mine's Black,not green) and it was NOT TIGHT...turned it full turn & 1/2...now, it is dang tight!...the new gas cap is the NON-vented type....so, I think you great minds have given me hope . The "Check Engine" light, IS NOT a pretty light, THANKS, Bill
Look for the pipe being properly attached to valve on the side of the motor. After I installed my LS6 manifold I did not get the pipe on all the way and got that code, along with a horrid gas stench when I parked the car.
Thread Starter
Burning Brakes
Joined: Jan 2006
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From: Magnolia Greens NC
Originally Posted by dpd
don't jump yet,that cap should be green.you may have the wrong cap.
Drifting
Joined: Oct 2003
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From: bloomfield nj
Originally Posted by trussme
Dang it!...twas the wrong cap. My "Green" Cap is very tight & secure. Now I'm back to ground zero..We've physically checked all lines & come up with "Duh?"....now appears the best way is a $75 "Smoke Test" , which is the only sure way to see where this demon is hiding. P0440 is the only code ( thanks to our US Govt. ) that I get...and our Emissions Testing in NC will excuse two codes. Everything else on this Vette is Perfect...except the Driver...
go under the car on the right hand side near the gas tank you will see the evap[charcoal]canister with 3 hoses on it.1 goes from the canister to the tank,1 goes to the purge valve,the other goes to the vent valve.if all the hoses are ok and the electrical connector is ok theb vent valve could be bad.when the car performs the test and applys a vacuum to the tanks the evap valve is open and the vent valve must be closed.if the vent valve is stuck open,it won't allow a vacuum to be applied.
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Burning Brakes
Joined: Sep 2004
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From: Havelock, NC ( NJ Resident )
Originally Posted by dpd
go under the car on the right hand side near the gas tank you will see the evap[charcoal]canister with 3 hoses on it.1 goes from the canister to the tank,1 goes to the purge valve,the other goes to the vent valve.if all the hoses are ok and the electrical connector is ok theb vent valve could be bad.when the car performs the test and applys a vacuum to the tanks the evap valve is open and the vent valve must be closed.if the vent valve is stuck open,it won't allow a vacuum to be applied.
w/dpd
Thread Starter
Burning Brakes
Joined: Jan 2006
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From: Magnolia Greens NC
Code 440 Issue
Originally Posted by dpd
go under the car on the right hand side near the gas tank you will see the evap[charcoal]canister with 3 hoses on it.1 goes from the canister to the tank,1 goes to the purge valve,the other goes to the vent valve.if all the hoses are ok and the electrical connector is ok theb vent valve could be bad.when the car performs the test and applys a vacuum to the tanks the evap valve is open and the vent valve must be closed.if the vent valve is stuck open,it won't allow a vacuum to be applied.
Drifting
Joined: Oct 2003
Posts: 1,540
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From: bloomfield nj
the vent valve is part of /attached to the charcoal canister.you can't miss it.the car will only do the evap/tank test if the fuel level is between a 1/4-3/4,if you are above or below,it will not perform the test.with your fault you either have a hose that's off or one that has a hole in it that is big enough to see,or the vent valve is not closing[you said you've replaced the gas cap with a known good/correct cap].
the vent valve keeps the gas tank from collapsing.
the vent valve keeps the gas tank from collapsing.
Last edited by dpd; Feb 1, 2006 at 07:23 AM.
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,170
Likes: 27
From: Magnolia Greens NC
Originally Posted by dpd
the vent valve is part of /attached to the charcoal canister.you can't miss it.the car will only do the evap/tank test if the fuel level is between a 1/4-3/4,if you are above or below,it will not perform the test.with your fault you either have a hose that's off or one that has a hole in it that is big enough to see,or the vent valve is not closing[you said you've replaced the gas cap with a known good/correct cap].
the vent valve keeps the gas tank from collapsing.
the vent valve keeps the gas tank from collapsing.