Interior - Popping or Thump Noise from Left Rear
File In Section: 6E - Engine Fuel & EmissionBulletin No.: 73-63-12
Date: June, 1997
INFORMATION
Subject:
Popping or Thump Noise from Left Rear of Vehicle
Models:
1996-97 Buick LeSabre
1996-97 Oldsmobile Eighty Eight
1996-97 Pontiac Bonneville
with 3.8L Engine (VIN K - RPO L36)
On some of the above listed vehicles, a subtle popping or thump noise may be heard coming from the left rear of the vehicle during the first 3 to 5 minutes after a cold start.
This noise occurs during a cold start OBD II fuel system vacuum leak check and should be considered a normal condition.
No corrective action is necessary. Do not replace any fuel system components, including the fuel tank. The tank noise will not cause any loss of functional performance of the fuel system.