Hi I have a 2000 hyundai accent with a engine light on it is code p 1128 fuel system lean part load, I have checked for vacuum leaks and I have cleaned the throttle body, also I have clean the mass air flow sensor, the car runs fine. What else should I check?
Replace the MAF. Quite common for it to cause problems when it is not working correctly without throwing trouble codes indicating it is faulty. Someone had replaced 3 MAF to finally resolved the probem.