2002 Chevy Cavalier P0172 system to rich

P0172 running rich probable causes include a bad O2 sensor, excessive fuel pressure (bad fuel pressure regulator or plugged return line), leaky fuel injectors, dirty air filter or restricted air inlet, or a defective coolant sensor that prevents the engine management system from going into closed loop mode.

I have replaced the air filter and the scanner is showing that it is running in closed loop when the freeze frame data is recorded, I also pulled the vacuum line from the fuel regulator and it is dry so the diaphram is good.

Problem FIXED!

I read in a troubleshooting tree that you can reset the fuel trims, I just diconnected the battery for a few mins and the problem is cured the light has not come back on for several weeks now. The code scanner just erased the codes but did not reset anything. With the old fuel pump not pumping enough fuel the fuel trims had adusted to compesate for a weak pump, When I put in the new pump the injectors were trying to undercompensate which was sending the the code PO172 system to rich.