Hey guys, first post. My girlfriend has a 1999 gs300 and initially it pulled up a p0155 code, I replaced it and reset the codes (it said heater malfunction and faulty signal) and it stayed off for about 5 months. It came back in and She ran it a while with the code on, knowing it was the o2 sensor. When I pulled them again it said p0155 and p0135 (bank 2 sensor 1 and bank 1 sensor 1) bank 2 being the reoccurring code. I tested both sensors with a multimeter and both produced voltage variations. After replacing both sensors (1 under warrantee) and clearing the codes, p0155 came back but p0135 in bank 1 remained clear. I'm at a loss! I checked the connections as best as I could but I'm not awfully familiar with these 2j's..yet! Any suggestions? Fuses, ecu flash...anything, thanks!

 

...Anyone?