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Inspection diagnostic wont check

I have a 2004 Dodge Stratus which I just brought in for inspection. When they connect that little handheld testing device (I guess for emissions, etc.) it confirms and O.K’s all parameters except two. It doesn’t say whether these parameters (O/2 sensor and catalytic) are good or bad, it just doesn’t even test them. I’ve driven the car over 600 miles on the advice of my mechanic to try and reset the computer but to no avail. He’s totally stumped and my 10 day temporary inspection is now about 40 days expired. Any suggestions I could give my mechanic or do I have to bring it to a Dodge dealer to run diagnostics, which cost $90? Any help and/or suggestions would be greatly appreciated. THANX!!

This is the generic drive cycle to reset the readiness monitors for your vehicle.

  • Start the engine cold and idle in drive with the AC and rear defroster on for 2 1/2 minutes.

*Turn off the AC and rear defroster and accelerate to 55 MPH at 1/2 throttle.

  • Drive at a steady speed of 55 MPH for 3 minutes.

*Allow the vehicle to slow down without using the brake to 20 MPH.

*Accelerate to 55-60 MPH at 3/4 throttle.

*Drive at a steady speed of 55-60 MPH for 5 minutes.

*Allow the vehicle to slow down without using the brakes.

*While the vehicle is just barely moving in gear, place the transmission into neutral and allow the vehicle to come a complete stop.

*Put the transmission in park and turn off the engine.


The diagnostic system on your car is constantly checking various emissions/fuel injection systems while you drive, like oxygen sensors, EGR, catalytic conveter, etc. These are called “monitors.” If the driving you have done does not provide the correct conditions for the car to run these monitors, the readout will show “not complete” rather than pass or fail. Your mechanic should have the technical ability and resources to determine why the O2 sensor monitor has not completed. Could be a faulty sensor, could be a software issue, could be that one of the conditions required to run the O2 monitor is not being met.

The catalyst monitor requires that the O2 monitor has completed and passed so I think one issue is causing both your problems.

Your mechanic should be giving you ideas rather than the other way around. $90 for a dealership diagnostic sounds fair, what does your mechanic charge you? I can’t imagine it’s much less. This may also involve leaving the car with your shop overnight.

Thanx to both of the readers of my posts. I’ll let you know what hapens. THANX!!! again