FLOOR PAN VIBRATION/MOAN NOSIE MODIFY AIR LINE TO CAT. CONV

MODELS AFFECTED: 1983 Centurys Equipped With 3.0L Engines

A floor pan vibration and moan at about 1900 engine RPM has been traced to two (2) conditions dealing with the catalytic converter air injection line attachment to the underbody.

Using the following repair procedure will correct this condition.

1. With car raised on hoist, remove screw which retains the catalytic converter air injection line at the floor pan and heat shield (See Figure 1) and cut off mounting tab.

2. Loosen hose clamp, separate air hose from air pipe. Cut 1/2" from air hose. Reinstall hose to air pipe and retighten hose clamp.

3. Modify new clip, part number 25515259 by bending upward as shown in View A, Figure 1. Install insulator part number 10016079 with this clip and reassemble to floor pan and heat shield. It may be necessary to bend the tab on the floor pan and heat shield for proper clearance. Make sure air pipe does not ground out on underbody and that the hose is not too close to the exhaust pipe.

4. Locate the area shown in Figure 2 which is immediately forward of the previous location. Add two (2) grommets part number 10016079 with straps part number 3816659 at location shown in Figure 2 to minimize ground out to underbody.

WARRANTY INFORMATION

Operation T5060 Time 0.5 Trouble Code 92

Parts Required 3 Grommets Part No. 10016079 1 Clamp Part No. 25515259 2 Straps Part No. 3816659

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.