Evap Bypass Not Opening WHY???
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Evap Bypass Not Opening WHY???
I have a P1456 code. I do not have any vacuum leaks (internal or external). CNS, PURGE, BYPASS, all work by grounding wires on the ECM.
When driving, the FTP is not showing any sudden changes to indicate that vacuum is being pulled on the tank. However, with the CNS valve closed and the BYPASS valve open, the PURGE DOES PULL VACUUM ON THE SYSTEM.
So, the purge is opening, but the bypass is not (unless I make it). What would cause this? Is a bad ECM the only possibility?
When driving, the FTP is not showing any sudden changes to indicate that vacuum is being pulled on the tank. However, with the CNS valve closed and the BYPASS valve open, the PURGE DOES PULL VACUUM ON THE SYSTEM.
So, the purge is opening, but the bypass is not (unless I make it). What would cause this? Is a bad ECM the only possibility?
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RoscoeT
Honda Accord (1990 - 2002)
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Jul 25, 2015 09:12 PM