Quote:

There are no codes, but the sensor is not getting a reading from the 4 following sensors...

1)O2S (Both 02 sensors plugged in and connections good, no frayed or cut wires)

2)CAT (If this is the catalytic converter, I had no idea it had a sensor other than the o2's)

3)HTR (I'm assuming is the heater, but is working fine)

4)EVAP





This is simply an indication by your scanner that the specific OBDII drive cycle tests for these subsystems has not been performed yet. Nothing more, nothing less. These are part of the OBDII READINESS MONITORS suite.

BTW, the EVAP system applies to the Contour. Trust me, I found out the hard way this past winter (P0442 code)....


I'd focus on several things first:

Clean the IAC. It is responsible for dashpot control. That is, it's supposed to allow a continuous amount of air to bypass the closed throttle plate during closed throttle decelleration. If you're getting the stumbling during partial throttle decelleration, it's probably not the IAC.

Uncommanded EGR flow come to mind as a possibility. Disconnect and plug the vacuum line to the EGR valve to see if the control system is at fault (you will likely set an EGR fault code doing this..)

A P0420 code means the cat has failed the oxygen storage test. By itself, it isn't particularly indicative of a flow-restricted cat. Cats with that condition typically exhibit a loss of accelleration. I'd also connect a vacuum guage to the intake manifold and look for low vacuum, a common indicator of a restricted exhaust. Removal of the upstream O2 sensor as mentioned is a quick and dirt (but noisy and dangerous) method of checking for restriction.


Steve

98 Contour SE Sport 2.5 Duratec ATX The wifey's car 89 Taurus SHO - 246K miles 94 SHO ATX - 190K 1997 F-150 5.4L ATX - The Workhorse 150K. ANY THREAD WITH "OMG" or "WTF" ETC IN THE TITLE WILL BE IGNORED!