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I did a mini me swap on my 99 Civic LX. Everything is working good except for the pending P0136 CEL that eventually add a P0138. I still using my old exhaust manifold (from the stock LX) and change the secondary O2 sensor twice, first with the generic ebay sensor, then this time I just installed a Denso and still getting the pending P0136. The voltage reading on the secondary sensor is 1.275v. I wired the secondary o2 sensor direct to ECU.
Any suggestions I can do to fix this problem. My car registration is due this month and I need a smog check. Please help!!!
Thanks