The check engine light comes on when the OBD-II (On board diagnostic monitirs) detect a fault.
In your case it probably was OBD-II code "P0303"
The light will not go off by itself.
They should have cleared the check engine light so it would be "off".
I would take it back to them and show them the check engine light still on and see what they say...could have just been an oversight.
You can do it yourself if you want by taking the negative post off the battery, wait 10 seconds and put it back on (IT WILL THEN BE OUT) but that might void any work guarantee that was completed, it's up to you. Also, you will neeed to reset all you settings radio, etc. etc.
There is a certain drive procedure that should be followed to clear the OBD-II (On board diagnostic) monitors. Here it is:
Generic OBD II "Drive Cycle"
Most OBD II ("On-Board Diagnostics II") diagnostic monitors will run at some time during normal operation of the vehicle.
However, to satisy all of the different Trip enable criteria and run all of the OBD II diagnostic monitors, the vehicle must be driven under a variety of conditions. The following drive cycle will (theoretically) allow all monitors to run on (??) vehicle. (Note: Drive cycle specifics vary by vehicle!)
1.Ensure that the fuel tank is between 1/4 and 3/4 full.
2.Start cold (below 86°F /30°C) and warm up until engine coolant temperature is at least 160° F (typically requires at least one minute; up to 3 minutes).
3.Accelerate to 40-55 MPH at 25% throttle and maintain speed for five minutes.
4.Decelerate without using the brake (coast down) to 20 MPH or less, then stop the vehicle. Allow the engine to idle for 10 seconds, turn the key off, and wait one minute.
5.Restart and accelerate to 40-55 MPH at 25% throttle and maintain speed for two minutes.
6.Decelerate with using the brake [or the clutch!] by coasting down to 20 MPH or less, then stop the vehicle. Allow the engine to idle for 10 seconds, turn the key off, and wait one minute.
Start it up and it's done.
Good Luck;
Rick
Dec 12, 2009 at 11:15 PM
