Astra L4-1.8L (2009)
Transmission Mount: All Technical Service Bulletins
Engine - Rough Idle or Bump Noise While Driving
TECHNICAL
Bulletin No.: 09-06-01-008
Date: June 15, 2009
Subject: Rough Idle or Bump Noise from Engine While Driving (Inspect Front Engine Mount Condition - Normal Condition)
Models:
2008-2009 Saturn Astra
Equipped with Automatic Transaxle (RPO MNF)
Attention:
This condition may be caused by the standard transmission neutral "bump" that is felt in vehicles equipped with the MNF (AF-17) automatic
transmission. Closer inspection of the vehicle may reveal that the condition the customer is experiencing is
normal when compared to a like vehicle or another engine/transmission mount may be damaged. The front engine mount should not be replaced for any
bump or noise concern.
Condition
Some customers may comment on a rough idle or a bump noise from the engine while driving. Upon further inspection, a technician may also identify
one of the three powertrain mounts are damaged and not operating as designed.
Correction
Note
A technician may observe what appears to be a broken mount located between the front of the transmission and the vehicle's subframe. This mount
is used primarily as an alignment tool for the assembly plant and as a motion limiter for the powertrain.
1. Inspect the engine and transmission mounts. Refer to Engine Mount Inspection in SI.
2. Closely inspect the vehicle front engine mount. This mount is used primarily as an installation aid from the factory. After vehicle assembly, the
locating tabs (1) are designed to separate, allowing the mount to act as a motion limiter. It is a normal condition for the motion limiter (1) to
appear to be broken. This is not abnormal and the mount should not be replaced unless:
-
It is physically damaged or worn significantly.
-
The hard rubber is covered with heat check cracks.
-
The rubber is separated from the metal plate of the engine mount.
-
The rubber is split through the center of the engine mount.
Important
The mount should not be replaced for any bump or noise concern.
If the front engine mount has any of the condition listed above, replace the front engine mount with GM P/N 90538576. Refer to Front Mount
Replacement in SI.
Parts Information
Warranty Information
