I OWN A 07 ZO6 WHOS HAD THIS PROBLEM NOW FOR AWHILE.
SOMEHOW THE DEALER CANT FIGURE OUT WHY THE FLAPS FROM EXHAUST ARE STAYING OPEN(LOUDER).
ALL THE LINES FROM ENGINE BAYTO THE REAR WERE REPLCACED, THE SELENOID BEHIND PASSENGER SIDE REAR LIGHT WAS REPLACED/FUSES CHECKED/VACUUM TO THE 2 CANISTERS WERE CHECKED AND OK.
WHAT TO DO?????????????

 

Have you checked the fuse?

 

not much to figure out, minimal parts in the system, find a new service center

 

Are the actuators functional?

 

My guess is electical, try cutting the wire to the solenoid and touching the ends together and see if any changes occur, and supply 12v to the solenoid to see if it is activating.

 

Did check the fuse, its fine.

It might be electrical.

 

Have a competent tech check it out by following the Exhaust Tail Pipe Flow Valve Mechanical System Diagnosis found in Document ID: 1715020. There are 36 steps to follow, all very straight forward.



Document ID: 1715020
Exhaust Tail Pipe Flow Valve Mechanical System Diagnosis

System diagnosis includes reviewing the system Exhaust Tail Pipe Flow Control System Description and Operation . Reviewing the information will help determine when a malfunction exists. It will also help to determine if the condition described by the customer is a normal system operation. Refer to Symptoms - Engine Exhaust in order to identify the correct procedure for diagnosing the system.
A Scan Tool can be used to command the vacuum solenoid On or Off.
Step
Action
Values
Yes
No
Schematic Reference: Exhaust Tail Pipe Flow Control Vacuum System
1
Did you perform the Diagnostic Starting Point - Exhaust Flow Control System?
--
Go to Step 2
Go to Diagnostic Starting Point - Exhaust Flow Control System

2

1. Important: Engine is NOT running.
   <LI type=1>Looking into the inboard tail pipes, verify that the exhaust flow control valves are both in the OPEN position. Caution: Refer to Exhaust Service Caution in the Preface section.
   <LI type=1>Manually rotate the each valve to the closed position.
2. Release the valves and allow spring tension to return the valves to the OPEN position.

Do both valves rotate CLOSED smoothly, without binding, and then return to the OPEN position when manual force is removed?
--
Go to Step 3
Go to Step 28

3

1. <LI type=1>Start the engine and allow it to idle.
2. Verify that both exhaust flow control valves rotate to the fully CLOSED position.

Did both valves close?
--
Go to Step 4
Go to Step 6
4
Use a scan tool to command the exhaust flow control solenoid OFF.
Do both exhaust flow control valves Open?
--
Go to Step 5
Go to Step 21

5

1. <LI type=1>Use a scan tool to command the exhaust flow control solenoid ON. <LI type=1>View both exhaust flow control valves from the rear of the vehicle.
2. Have an assistant depress the accelerator pedal to the floor and immediately release the pedal.

Did the exhaust flow control valves remain fully CLOSED?
--
Go to Step 36
Go to Step 24

6

1. <LI type=1>Disconnect the quick connect between the vacuum check valve and the front chassis vacuum pipe, located near the brake booster. Important: If the O-ring is damaged, the exhaust tail pipe flow control vacuum check valve and hose will need to be replaced. Refer to Exhaust Tail Pipe Flow Control Vacuum Check Valve and Hose Replacement .
   <LI type=1>Inspect the quick connect O-ring .
2. Using a vacuum gage at the vacuum check valve, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 7
Go to Step 14
7
With the engine running, clamp off the rubber vacuum hose forward of the vacuum check valve.
Does the vacuum gage read steady within the specified range for 30 seconds?
16-30 in Hg (54-102 kPa)
Go to Step 8
Go to Step 29

8

1. <LI type=1>Remove the clamp from the vacuum hose. Important: If the O-ring is damaged, the line reservoir tank to control valve solenoid pipe will need to be replaced. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Reservoir Tank to Valve Solenoid .
   <LI type=1>Disconnect the chassis rear vacuum pipe from the reservoir tank to valve solenoid pipe quick connect . Located under the vehicle at the from edge of the rear bumper.
2. Using a vacuum gage at the chassis rear vacuum pipe, measure and record the vacuum signal at engine idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 9
Go to Step 15

9

1. <LI type=1>Connect chassis rear vacuum pipe from the reservoir tank to valve solenoid pipe quick connect . Important: If the O-ring is damaged, the line reservoir tank to control valve solenoid pipe will need to be replaced. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Reservoir Tank to Valve Solenoid
   <LI type=1>Disconnect the vacuum pipe from the vacuum tank.
2. Using a vacuum gage at the pipe, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 10
Go to Step 17

10

1. <LI type=1>Disconnect the vacuum pipe from the left flow control valve.
2. Using a vacuum gage at the pipe, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 11
Go to Step 18
11
Using a J 35555 Metal Mityvac at the left flow control valve, apply at least 16 in Hg (54 kPa).
Does the left flow control valve close?
--
Go to Step 12
Go to Step 28

12

1. <LI type=1>Disconnect the vacuum pipe from the right flow control valve.
2. Using a vacuum gage at the pipe, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 13
Go to Step 33
13
Using a J 35555 at the right flow control valve, apply at least 16 in Hg (54 kPa).
Does the right flow control valve close?
--
Go to DTC P166A
Go to Step 28

14

1. <LI type=1>Connect the vacuum check valve and the front chassis vacuum pipe. <LI type=1>Disconnect the vacuum hose at the vacuum check valve.
2. Using a vacuum gage at the vacuum hose , measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 29
Go to Step 19

15

1. <LI type=1>Connect the vacuum hose to the vacuum check valve. Important: If the O-ring is damaged, the rear chassis vacuum pipe will need to be replaced. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Chassis Rear .
   <LI type=1>Disconnect the rear chassis pipe from the reservoir tank to valve solenoid pipe, located left of the transmission.
2. With the engine running, use a vacuum gage at the front chassis pipe, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read steady within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 16
Go to Step 30

16

1. <LI type=1>Connect the pipes. Important: If the O-ring is damaged, the rear chassis vacuum pipe will need to be replaced. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Chassis Rear .
   <LI type=1>Disconnect the quick connect in the rear chassis vacuum pipe, located above the transmission.
2. Using a vacuum gage at the forward part of the rear chassis vacuum pipe, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 31
Go to Step 36

17

1. <LI type=1>Connect the quick connect.
2. Disconnect the vacuum reservoir tank to valve solenoid from the vacuum valve solenoid.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 34
Go to Step 32

18

1. <LI type=1>Disconnect the chassis rear vacuum pipe from the reservoir tank to valve solenoid pipe quick connect . Located under the vehicle at the from edge of the rear bumper. <LI type=1>Disconnect the reservoir tank to valve solenoid pipe from the vacuum solenoid.
2. Using a J 35555 apply at least 16 in Hg to reservoir tank to valve solenoid pipe.

Can 16 in Hg of vacuum be achieved?
--
Go to Step 32
Go to Step 23
19
Check for restrictions between the intake manifold port the vacuum check valve.
Did you complete the repair?
--
Go to Step 36
Go to Step 20

20

1. <LI type=1>Disconnect the vacuum hose at the intake manifold.
2. Using a vacuum gage at the intake manifold, measure and record the vacuum signal at engine Idle.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
--
Go to Diagnostic Starting Point - Engine Mechanical for the 7.0L engine
or
Diagnostic Starting Point - Engine Mechanical for the 6.0L engine
21
Disconnect the vacuum pipe from the left exhaust flow control valve . The left valve will open.
Did the right exhaust flow control valve also fully OPEN?
--
Go to Step 34
Go to Step 22
22
Disconnect the vacuum pipe from the left exhaust flow control valve.
Did the both exhaust flow control valves fully OPEN?
--
Go to Step 33
Go to DTC P166A

23

1. <LI type=1>Disconnect the reservoir tank to flow control valves pipe from the vacuum solenoid.
2. Using a vacuum gage , measure and record the vacuum signal at engine idle from the vacuum solenoid.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to Step 33
Go to Step 32

24

1. <LI type=1>Disconnect the vacuum check valve from the front chassis vacuum pipe, located near the brake booster. Important: If the O-ring is damaged, the exhaust tail pipe flow control vacuum check valve and hose will need to be replaced. Refer to Exhaust Tail Pipe Flow Control Vacuum Check Valve and Hose Replacement .
   <LI type=1>Inspect the O-ring. <LI type=1>Using a vacuum gage, measure and record the vacuum signal at engine Idle from the vacuum check valve.
2. Clamp off the rubber hose forward of the vacuum check valve.

Does the vacuum remain steady for 30 seconds?
--
Go to Step 25
Go to Step 29

25

1. <LI type=1>Remove the clamp. <LI type=1>Remove the vacuum gage. <LI type=1>Connect Quick the vacuum check valve to front chassis pipe. <LI type=1>Disconnect the vacuum pipe from the reservoir Tank.
2. Using a J 35555 apply vacuum to the reservoir tank.

Does the vacuum gage read within the specified range for 30 seconds?
16-30 in Hg (54-102 kPa)
Go to Step 26
Go to Step 35

26

1. <LI type=1>Connect the vacuum line to the vacuum tank. <LI type=1>Using a vacuum gage, tee into the vacuum lines at the left exhaust flow control valve. <LI type=1>Use a scan tool to command the exhaust flow control solenoid ON. <LI type=1>View both exhaust flow control valves from the rear of the vehicle.
2. Have an assistant depress the accelerator pedal to the floor and immediately release the pedal.

Does the vacuum gage read within the specified range?
16-30 in Hg (54-102 kPa)
Go to DTC P166A
Go to Step 27
27
Isolate a small leak in the following locations.
Did you complete the repair?
--
Go to Step 36
--
28
Replace the exhaust flow control valve. Refer to Exhaust Muffler Replacement - Left Side or Exhaust Muffler Replacement - Right Side .
Did you complete the repair?
--
Go to Step 36
--
29
Replace the engine vacuum line assembly. Refer to Exhaust Tail Pipe Flow Control Vacuum Check Valve and Hose Replacement .
Did you complete the repair?
--
Go to Step 36
--
30
Replace the forward chassis vacuum line. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Chassis Front .
Did you complete the repair?
--
Go to Step 36
--
31
Replace the vacuum line between quick connect 3 and quick connect 4. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Chassis Rear .
Did you complete the repair?
--
Go to Step 36
--
32
Replace the solenoid vacuum line. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Reservoir Tank to Valve Solenoid .
Did you complete the repair?
--
Go to Step 36
--
33
Replace the vacuum line between the vacuum solenoid and exhaust flow control valves. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Replacement - Valve Solenoid to Control Valves .
Did you complete the repair?
--
Go to Step 36
--
34
Replace the vacuum solenoid. Refer to Exhaust Tail Pipe Flow Control Valve Solenoid Replacement
Did you complete the repair?
--
Go to Step 36
--
35
Replace the vacuum storage tank. Refer to Exhaust Tail Pipe Flow Valve Vacuum Pipe Reservoir Tank Replacement .
Did you complete the repair?
--
Go to Step 36
--
36
Operate the system in order to verify the repair.
Did you correct the condition?
--
System OK
Go to Step 2

© 2008 General Motors Corporation. All rights reserved.

 

Uh? Why the hell would you do that?? At best all this will accomplish is blow a fuse and give you a car with a severed plug...
If you think your battery is dead, do you put a wrench across the terminals too just to check?
You know, they make these little devices called "multimeters" that will tell you if a circuit is live or not without requiring that wires be severed and without placing a direct short on your electrical system... Radio Shack carries them

 

Which fuse?

 

Bottom right in the pass well

10A = marked exhaust