Complaint Complaint A: The engine is jolting/bucking between 1700 and 1900 rpm

Bulletin number

LI14.20-N-073867

Component

Power train

Summary

Complaint Complaint A: The engine is jolting/bucking between 1700 and 1900 rpm. Complaint B: One or more mechanical related fault codes for EGR Valve stored in CDI control unit, with possible Check Engine Light. Review list of mechanical fault codes in table below. NOTE: If one or more electrical related fault codes for EGR Valve are also present in CDI, utilize Complaint C. Review list of electrical fault codes PDF document in attachments. Complaint C: One or more electrical related fault codes for EGR Valve stored in CDI control unit, with possible Check Engine Light. Review list of electrical fault codes PDF document attached. NOTE: This LI supersedes LI14.20-N-073813, which is no longer valid. Cause Cause of Complaint A: Increased friction between the EGR Valve blade and seat due to soot deposits causing a delay of the EGR Valve being able to reach the target value of the EGR Valve position controller. NOTE: This causes the EGR Valve blade and potentially the boost pressure controller to oscillate. Cause of Complaint B: Soot deposits between the EGR Valve blade and seat leading to the EGR Valve no longer being able to meet the de-sired target of the EGR Valve position controller. Cause of Complaint C: Internal EGR Valve or other electrical faults related to the EGR Valve function. Remedy Remedy for Complaint A: Perform the following steps: 1. Disable the EGR Valve (Y27/17) by disconnecting the electrical connector. 2. Perform a test drive to check if the jolting/bucking issue resolves. 3. If the jolting/bucking is resolved, proceed to Remedy for Complaint B. 4. If jolting/bucking is still present, proceed with diagnosis to determine the root cause. Consider checking the follo-wing, but not limited to: •EGR system including the EGR Cooler, EGR Bypass Flap, EGR Temperature Sensor, and pipes for proper operati-on, excessive sooting and/or clogging, as well as EGR Bypass Flap vacuum element, switchover valve, and vacuum system. •Visually check the leak oil line or T-piece; reference LI07.00-N-059118.

Owners of these vehicles have filed 111 complaints in the transmission category.