Check engine light 13

Hi all. I'm new to the forum and after some help. I have a v reg jimny which keeps throwing up a check engine light. I used the box under the glove box and got code 13 to flash up. Using this site I found previous faults similar which point at a faulty o2 sensor. I changed the 02 sensor and it seemed fine untill I hit a hill and put my foot down to get up it,and the light came on again. Jimny runs fine just burning more fuel.

Could I be really unlucky and fitted another dodgy o2 sensor or do you think some thing else?
Regards
Luke

think ours has 2 o2 sensors before and after the cat

Well since my last post iv done some more digging and found that the 02 sensor is fine. However I have checked the loom when the lambda sensor is disconnected and found that I have continuity between the earth and poss cables. I have followed the cables back to the engine bay grommet and still have continuity. So it's looking like it may well go all the way back to the ecu? Does anyone know of this happening in ecu?

I replied to your PM. It would be unusual to have a short on the sensor input, its designed to be very robust. The output to the heater is more difficult to protect and protection is only mandated on newer ECUs, however the main fuse usually blows if the heater goes short circuit.

Hello all from the land of Oz
I have the same issue with my 99 jimmy runs well just low on power fault points to O2 censor but tests fine, my local Suzuki dealer has had the same problem with a Vitara for 12 months and can not find the problem. Hoping that someone there has a solution
Mr Fitz

How are you testing the O2 sensor? what do the fuel trims look like?