I have a 2004 Mazda 6 wagon with the 6 cylinder engine. Check engine light had codes for both running too rich and running too lean. I found my air hose to be craked and repaired with duct tape. I cleared codes by disconnecting the battery and drove for a few days problem free. CEL came on again and reset itself the next day. Again I drove problem free with no light for almost a week and when I went to get the car inspected (North Caorolina) as soon as they hooked up the OBDII the light came back on with the running too lean code. After I left, the light once again turned itself off and again I ran for a few days before I revisited the inspection station. Same thing happened. As soon as the OBD II was hooked up on came the light. How long do I need to wait or is there a way of clearing codes to have it not show old codes?

 

First off, replace the hose. Repairing it with duct tape works to get you down the road to the dealership, but it is not a permanent fix nor will it seal as well as a new hose. That said to clear your codes you simply unplug the batt for a little while, that will clear all old codes.

 

I've got you on the new hose, but if I unplug the battery then I just get computer not ready. I tried that today and even after about 75 miles and 8 to 10 starts still getting computer not ready status.

 

No clue what to tell you there man. Sorry.