Ive got GMS1 and a Bad Mab catless DP with Modern Performances 02 defouler and I just started to get a P0140 code come on...ive had this setup for 4 months with no issues until now...it happens once the car has been running for aprox 15 mins then i clear it and its good until the car is shut off and started again...just wondering if anyone else has had this issue and if soo what fixed the prob...

 

A catalytic converter would fix it.

 

P0140 is no circuit to the rear sensor. Meaning the sensor probably got screwed up when putting on the dp. broken wires or something like that more than likely. If you replace the o2 sensor it should be good to go. Having that code isn't going to hurt anything tho

 

yea it reads no activity on my scanner and your right theres no harm its just annoying! ill grab a new sensor this week and try it out