Bosch LSU 4.9 sensor goes bad after two tanks of fuel

[ZD302GT]

Hey guys I'm really needing some help diagnosing what could be killing my widebands so quickly, I cant keep changing them out every other tank. Any suggestions on places to investigating would be very helpful. My newest one just went bad and I don't want to put a fresh one in there before I figure out what is happening.

The only things that I can think of that may potentially hurt it are as follows.
1. Winter Stabil in the tank
2. 20 year old valve seal smoke at startup
3. sensor in a rear O2 bung

I run an aeroforce gauge and their controller.

Thanks!

 

[moncho]

It should be installed/orientated between 10 & 2 o'clock, keeps condensation from forming & killing the sensor. Preferably pre-cat for better accuracy. Also, turn ignition key on for a few seconds before turning the car on, allows sensor to warmup some.

Good Luck!

 

[ZD302GT]

Ya the bung that its in is a tad higher than horizontal in the pipe.