Im testing the Oxygen sensor on my '80 245 today, and I've read the books so many times I've confused myself.

I get the car up to temperature (drove it around for a while), hook up the voltmeter (+) to sensor with it connected, and neg. to ground - it fluctuates around .5 volts fine....

Then I turn car off, disconnect sensor and connect voltmeter (+) to sensor, neg to ground. Start car and I get no voltage at idle (well maybe .002 volts or less).

If I raise the RPM's the voltage does increase, as high as .86 volts or so. But, doesnt the book say there should be a greater fluctuating voltage at idle?

Other minor details: the car "bucks" horrendously and I havent been able to keep the frequency valve duty cycle at a consistant level. (there may be several things going on here)


thanks for any response!
NOAH