My daughters boyfriend has a 2000 Hyundia Accent that keeps throwing a P1128 Manufactures specific power train code. I do not have any detailed information on this car so I am unable to determine the cause for the code to set. Does anyone have any in depth knowledge on this code that could lend a hand to help me figure it out. I reset the code with my scan tool and it stays off for a short time but comes back. The owner said he doesn't notice any abnormal operation. When the car was running I reset the code and it did affect the RPM and car sound slightly. Any help would be greatly appreciated.

Don

 

P1128 is a lean mixture part throttle, Check mass airflow and all hose's, check pcv hose. If all is ok the dealer has a reprogram for the ecm I believe.