o2 sensor heater relay blowing

[gtdragon980]

well after doing everything i possibly could to my car to get it to run correctly and get more than 100 miles on a tank, i've finally come down to the last problem with my car. i hooked a retriever up to the car and pulled a o2 sensor heater relay fault. after testing the fuse box and wires to look for a short, i found that whenever the o2 sensor is plugged in, it blows the fuse and blows the relay.if the o2 is unplugged, it will not blow. my question is, is it because im using the ford mustang 5.0 o2 sensor??i replaced my old one with this one not too long ago so its pretty new, although my car was running rich for half a year. i just replaced my fuel injectors so that should be gone, but now im wondering if this problem is really because the sensor is bad. could it be cause of differences between the bmw one and the ford one? is it just a fault sensor? any help is appreciated!!

[jlevie]

The definitive test would be to get and install an OE sensor.

[gtdragon980]

Damn, I guess I gotta fork out the cash then huh? Okay I'll see how it goes and return with results in a few days