Very good practical answer "aer auto repair". I had an intermittent problem on my BMW, I didn't want to carry around my oscilloscope and wrote what all the ac voltage readings should be for a "healthy sensor".
this obd2 trouble code table can help you understand the meaning of code. http://www.chinasinoy.com/service/how-to-understand-trouble-codes-37.html for this code, you can try the following solution: Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required. Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady). Inspect the downstream heated oxygen sensor (HO2), replace if necessary Replace the catalytic converter
thanks all the crank position sensor was working most of the time. it checked out ohlm wise and volt wise but changed it out and code p0322 went away and it doesn't die anymore but after driving it so long with the bad cam adjuster i think the valves are burnt or the turbo is sending oil out the exhaust and triping the p0420 code. if that is possible? but it's getting him to work now and maybe he can save enough to get a head job and replace the turbo. we cleaned out the sludge and the cams look fairly good and lifters also look good. was going to do a compression check to see if the turbo should be first on the list. it smokes but not bad I am not very versed on turbos on cars.
Ok lets start with the easy one p0420 Cat System Efficiency Below Threshold Bank 1 you most likely need a catalytic converter replaced. Now for p0322 (I am assuming you are mechanically inclined) Check all fuses. Test the connector for the G28 engine speed sensor at the firewall connection for corrosion or loose contact. At the connector for the ECM, check resistance between the two pins for the engine speed sensor. Pin number 82 has a Gray wire, and 90 has a Blue wire. The resistance reading through the sensor should be between 730 and 1000 ohms. If resistance is good, crank the engine and reading AC voltage between pins 82 and 90. The voltage reading should be greater than 1 V AC while cranking. If the Engine Speed Sensor fails either test above, it should be replaced. If you need our services we can be reached at firstname.lastname@example.org or 208-424-6717 hope this helps.