This cts-v has over 130k miles and original oxygen sensors. I switched to E85 about 6 month ago. Just recently I have been experiencing a surging when cold. During the first few minutes of startup, I get a new oscillation where my wideband goes lean to rich and the idle surges slowly. On this log it almost stalled, which makes me think its getting worse. After about 3-4 minutes of idle/run time, everything smooths out.
I noticed that once the O2 sensors reading tightens up, the AFR, idle and timing all smooth out. Should I toss some new Oxygen sensors in it?
22-12-25 18-25-28.hpl
CTSV with FPCM DW300 stock prv 65psi maf3.hpt
And yes, I know my FP is dropping in boost.