Ever thought that it might be a different code?
BankerBalt is correct. Not at all times does replacing a sensor and clearing codes will correct the issue. We have a few guys at our Ford shop who are considered "parts hangers". Sometimes by replacing the part/sensor may cause a chain reaction to other sensors. I have seen it a few times at work and its very troubling to tell a customer that and see their face get really mad. You may have triggered another code from replacing a sensor or that may have not fixed the issue. You have to understand that a code coming from the PCM doesn't always means "replace sensor". It could also mean open/short/high resistance to the sensor itself. Remember, your dealing with a computer based engine monitoring system and it has certain values that it needs to use in order to clear the code. Any interruption during 2 drive cycles will trigger the CEL to illuminate.
Clearing the code from your scan tool will not all the time fix it. It also may have to cycle through a few drive cycles in order to respond. Some cars require half tank gas, evap canister full, minimum of 40 miles driven per cycle, speeds of 45/65 mph required, just based on manufacturer too.
Here is a very helpful tip on PCM systems: It requires a signal input from sensor (sensor is an input to PCM), then gets calculated through PCM, then sends an output signal (output signal such as a valve, solenoid, actuator) and keeps this cycle going during your drive cycle. If ANY of this is not reading correctly during a minimum of 2 drive cycles, a CEL will illuminate (OBDII standard).
2009 Cobalt LS XFE U74
Mods: K&N Typhoon Intake, Option Cat-Back Exhaust, Cosmo Short shifter, Maxxim Ahead 17X7's, MPx shorty antenna, FE5 Strut/shocks, Tein S Techs, Moog endlinks, Moog spring seaters, ZZP shorty header, LSJ downpipe, LNF front grille
Last edited by 5t3alth; 02-27-2014 at 04:47 AM.