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· Registered
205 Posts
Discussion Starter · #1 ·
My check engine light came on, I scanned the codes with my cortex and it reads the following;
P0442 - Small Evap leak
P0455 - Evap gross leak
P2544 - Torque management request input signal A
I cleared these codes and as soon as I start it up, they come back on. I have searched through the archives and have not found anything about these cars giving these 3 codes at once. There is no noticeable difference when driving it. checked the fuel cap and intake fitment, no issues there. The only mods are Roto-Fab, cortex, and Magnaflow cat back. Any help would be appreciated.

· Premium Member
4,866 Posts
That's a first for me too (that 3 pack of codes). Thinking that if a large evap leak (p0455) had developed, it sounds like the small leak (p0442) wouldn't be able to run its test successfully after engine shutdown. Like if the evap purge valve did not open after engine start up to allow a certain amount of vacuum to enter the gas tank, the pressure sensor (in the tank), might interpret that as a large leak condition exists, an set that code. Then after shutdown, having the improper value of vacuum in the tank (in the first place), the car interprets that as a small leak condition (an set that code).
It says that the P2544 code picked off something wrong on the *can bus* (I think). But for it to record that fault, it required that it see some other fault or faults first (I think). Maybe those 2 other set codes, are the ones allowing that 3rd code to set.
It is very confusing for me to understand this thoroughly. This is the best guess I can figure out.
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