2000 chevy prizm check engine light

If you expect an intelligent answer post the code. Other wise it is all speculation like change the rear tires.....

System too lean means the computer thinks it must use more fuel than normal to maintain proper O2 readings.

Check for vacuum leaks. Check for broken or loose air intake hose between air flow sensor and throttle body. Check for anything else which might allow unmetered air to enter engine through intake. If all that appears ok, suspect the air flow sensor is bad.

Thanks for the help took it to toyoata dealership for them to look at and it turned out the 2 wires in the mass air flow sensor was gumed up with dirt , leaves ,sand , etc because of the air filter box not making a tight seal around the filter so it couldnt read the intake air correctly and caused it to run lean .switched to a filter with a softer edge and replaced mass air flow sensor light stays out and runs like brand new again ..