Exhaust Manifold and Front Tube Leak Check

1. Position the vehicle on a hoist ready to be lifted.

2. Turn the ignition OFF

3. Raise the vehicle on the hoist.





4. WARNING: Wait for the exhaust system to cool before touching exhaust system components. Hot exhaust components can cause severe burns.





5. Remove the cross brace shown in
Figure P2.

^ Cross brace is held on with 4 bolts, 2 on each side.





6. Unbolt the front exhaust tube hanger.

^ Hanger is held on with 2 bolts.





7. Unbolt the front exhaust tube from the center exhaust tube at the flange.





8. Attach an elastic strap (or other Front exhaust suitable support) under the rear of the tube front exhaust tube (see Figure P5).

NOTE:
The elastic strap should support the front exhaust tube when it is
disconnected from the center exhaust tube.

CAUTION:
Make sure exhaust tube has cooled enough not to burn the elastic strap or other support.

9. Disconnect the front exhaust tube from the center exhaust tube.
harness

NOTE:
Make sure the rear oxygen sensor harness is not stretched.

10. Let the elastic strap (or other suitable support) support the front exhaust tube.

CAUTION:
Make sure exhaust tube has cooled enough not to burn the tube elastic strap or other support.





11. Attach special tool J-50976 to the rear of the front exhaust tube as shown in Figure P7.

CAUTION:
Make sure exhaust tube had cooled enough not to burn the rubber seal on the tool.





12. Connect a shop air hose to special tool J-50976.





13. Set the valve on special tool J-50976 to the open position (see Figure P9b).

14. Attach a 19 mm socket with handle to the front pulley (see Figure P9a).

15. Position the engine crankshaft at the point of the highest pressure on the gauge as follows:

WARNING:
Make sure the ignition is OFF or the engine may turn on its own.

a. Watch the pressure gauge while slowly turning the engine (see Figures P9a and P9b).

^ Turn the engine clockwise (as you face the front of the engine).

b. When the pressure gauge is reading at the highest point (most PSI) stop turning the engine.

^ Highest pressure will be between 5 and 6 PSI.

16. Check for leaks as follows:

a. Turn the valve to the closed position.

b. The pressure will start to drop.

c. When pressure drops to 5 PSI, begin a 20 second count.

d. At the end of the 20 second count, read the pressure.

Go to OK/NG information

OK: Pressure is 2 psi or above; there is no leak in the front tube or manifold.

> If vehicle has more than 50,000 miles, go to Exhaust Manifold Replacement

> If vehicle has less than 50,000 miles:

^ Remove the exhaust manifold stay - see page 10.

^ Reinstall the front exhaust tube.

Use a new gasket between the front tube and the center tube.

Nuts for the front exhaust tube to center tube; torque to 14 N-m (1.4 kg-m, 10 ft-lb).

Bolts for front exhaust tube hanger; torque to 14 N-m (1.4 kg-m, 10 ft-lb).

Bolts for cross brace; torque to 21-29 N-m (2.1-2.9 kg-m, 15-21 ft-lb).

NG: Pressure is below 2 psi; there is a leak in the front tube, manifold, or gasket.

A. By feel and sound, locate the leak.

NOTE:
^ If needed, eliminate any air hiss noise from the air supply hose or the tool regulator by disconnecting the air hose from special tool J-50976.

^ If needed, use soap and water to confirm leak location.

B. Replace only the leaking part (gasket, front exhaust tube, and/or exhaust manifold).

NOTE:

For all vehicles with more than 50,000 miles, replace the exhaust manifold even if it does not have a leak.

^ Replacement of the exhaust manifold includes removal of the exhaust manifold stay.

> For a leak at the gasket between the exhaust manifold and front tube; refer to (Front Exhaust Tube Replacement) and replace only the gasket

> For a leak at the gasket between the exhaust manifold and engine head; refer to (Exhaust Manifold Replacement) and replace only the gasket

> For a leak in the front tube; refer to (Front Exhaust Tube
Replacement).

> For a leak in the exhaust manifold; refer to (Exhaust Manifold
Replacement).