So I had a wideband gauge decided to mess with it and accidentally broke it, bought another gauge same company same wiring diff style gauge. I hooked it up and when I first tested it I just turned the car to accessories didn't start it, wanted to test if I had it wired right. everything lit up and the gauge red 14.6 with the car off. When I start the car the gauge reads 19.9 and jumps between 19.8-19.9. I didn't jack the car up and swapped the sensor yet but I do have access to the harness where I can plug a new sensor in right from inside the car. I have a spare bosch sensor and I plugged it in, it also reads 19.9 but when I places a gas soaked rag over the 02 sensor it read 10. Which from my understanding and please correct me if I'm wrong, if the gauge can read 10 and then 19.9 that would eliminate it from being defective? So is my sensor bad or do I have an exhaust leak?

 

Did you calibrate it?

 

Which wideband are you using?

 

Yes i did reset the gauge and its prosport evo series, i had their analog version before and it worked perfect, the both use the same sending unit and the wiring is identical.

 

It should read 19.8-19.9 with the power on but the car not running. I have the Prosport Evo and that's what it does after its start up cycle.

While the stuff my look identical, the wiring internally may not be the same.

 

But if it was wired wrong would the gas soaked rag not pull up a 10.0 reading? When i took the rag off ot went back to 19.9

 

but did you calibrate it? Read your instructions. free air?

 

Did it stay 10.0? Also check all your grounds.

Again while the gauges may look similar, the internal wiring and voodoo witchcraft that goes on inside may not be identical, giving you erratic readings.

 

Update It was the 02 sensor, swapped it for a new one now gauge reads 14.7 at idle