EVAP still functioning?
Thread Starter
On The Tree
Joined: Sep 2012
Posts: 134
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From: New Taxes York
EVAP still functioning? Attached is a screen shot from Torque Pro as the car idles.
It's an LS2 from a GTO with the ECM flashed to remove VATS and emissions...
It shows the EVAP system still functioning. I assumed it was disabled during the reflash 2 years ago, but obviously not.
The EVAP solenoid and tubes have been removed and the two ports plugged. Is the fact that the EVAP system is still trying to function presenting a problem with fuel mileage or efficiency\performance? Short of removing the plugs and JB Welding the ports closed, is there still something that needs to be removed\disabled from the ECM? Or will EVAP always show functionality?
Thanks!
It's an LS2 from a GTO with the ECM flashed to remove VATS and emissions...
It shows the EVAP system still functioning. I assumed it was disabled during the reflash 2 years ago, but obviously not.
The EVAP solenoid and tubes have been removed and the two ports plugged. Is the fact that the EVAP system is still trying to function presenting a problem with fuel mileage or efficiency\performance? Short of removing the plugs and JB Welding the ports closed, is there still something that needs to be removed\disabled from the ECM? Or will EVAP always show functionality?
Thanks!
Thread Starter
On The Tree
Joined: Sep 2012
Posts: 134
Likes: 0
From: New Taxes York
When your tuner turned off your emmisions they only turn off the reporting code, so your PCM still runs the evap test, it just doesn't report that it fails. Since when it is running the test one of the things the PCM does is to reduce the injector pulse since it is expecting fuel enrichened air to enter the intake from the evap soleniod. To prevent this from happening you must tell the PCM that conditions aren't right to run the test. Since the test will only run between one quarter and three quarters of a tank of gas, you need to put a resister of the fuel gauge input that tells the PCM it is either less then one quarter tank or more then three quarters tank
When your tuner turned off your emmisions they only turn off the reporting code, so your PCM still runs the evap test, it just doesn't report that it fails. Since when it is running the test one of the things the PCM does is to reduce the injector pulse since it is expecting fuel enrichened air to enter the intake from the evap soleniod. To prevent this from happening you must tell the PCM that conditions aren't right to run the test. Since the test will only run between one quarter and three quarters of a tank of gas, you need to put a resister of the fuel gauge input that tells the PCM it is either less then one quarter tank or more then three quarters tank
Tipsy
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If you have HP tuners, go to Engine diagnostics, then DTC's and scroll down to P0442. That is the start of the Evap codes. Uncheck all 9 of the boxes 0442 thru 0455 and change the numbers to 3--not reported. That should effectively delete the evap system. (For offroad only) 
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Verdad Gallardo If you have HP tuners, go to Engine diagnostics, then DTC's and scroll down to P0442. That is the start of the Evap codes. Uncheck all 9 of the boxes 0442 thru 0455 and change the numbers to 3--not reported. That should effectively delete the evap system. (For offroad only)
Tipsy
If you have HP tuners, go to Engine diagnostics, then DTC's and scroll down to P0442. That is the start of the Evap codes. Uncheck all 9 of the boxes 0442 thru 0455 and change the numbers to 3--not reported. That should effectively delete the evap system. (For offroad only)