Throwing a 44 code

1991 Suburban with 350 TBI. Just bought it, so I changed the rotor, cap and wires. Everything seeemed to run OK for about a week, then I seemed to lost high end power -- seemed like the timing wouldn't advance enough while going up hills. The Check Engine light came on occasionally.

Pulled the codes and came up with only a 44 -- lean exhaust. In addition to replaceing the O2 sensor, I feel the problem could also be a plugged catalytic converter. Something seems to be holding the car back.

Need your help/opinions on the matter. Thanks in advance and happy Thanksgiving.

have you checked the fuel filter for restrictions? this will set a code 44

Success! Replaced the O2 sensor and the fuel filter. Both jobs took less than 45 minutes. The car now runs like a tiger. Thanks for the helpful advice.