Can any one tell me the symptoms when the lambda sensor goes wrong? I am running closed loop on a s8 ecu and the car was running rich with an erratic idle, i have checked things like map sensors, ignition amps, how can I check the lambda sensor functioning? , there are four wires on the lambda sensor the grey wire was wasn’t connected but when I connected this wire thinking that it maybe positive but the car cut out on doing this… is this the right wiring sequence. Black = ecu sensor wire number two on the port ecu plug. Two white one = positive the other white plus grey = negative.

Thanks

Sean

 

If the lambda is functioning then you will be able to see it on your S8 software flipping from rich to lean etc??

 

thats the only problem at the moment my laptop gone tits up

 

Ah, bugger!!

Well the S8 only needs one wire from the lambda and thats the signal wire to pin 2 on the ecu. The sensor itself needs a pos and neg for the heater. As for a 4 wire lambda, the other wire is probably signal ground so just earth it to the other neg wire? You probably need to find out what make your sensor is and do a search for wire colours/jobs. The signal wire off my 3 wire one is white!!!