Install my TXS stealthback and prodrive axelback with the Pony Express MIL Eliminator about two weeks ago. No problems with the install. Last week the CEL comes on. I have it check by the same person that did the install and this is the code that came up."P0136 O2 Sensor Circuit Range/Performance Problem - Malfunction (Bank 1 Sensor 2) "He said maybe the MIL is bad? He resets the ECU and a few days later the CEL is on again. Can the MIL be bad? Can it be something esle?The next off day I have we will look at the MIL.

 

Run a search on the P0136, there are a couple of good suggestions on how to fix that CEL.