Disclaimer***Acura Truck MDX V6-3.7L Technical Service Bulletin # 13-003 Date: 130130
Exhaust System - Front Cat. Converter Heat Shield Rattle, Buzz
13-003
January 30, 2013
Applies To:
2007-11 MDX - ALL
Front Catalytic Converter Heat Shield Rattles or Buzzes
SYMPTOM
There is a rattle or buzz from the engine compartment that is most noticeable at idle or under light acceleration.
PROBABLE CAUSE
There is a radiator drain access hole in the front lower splash shield where water and road salt can enter and splash onto the warm-up TWC (front
warm-up three way catalytic converter) heat shield. The heat shield may rust or corrode to a point where the shield is loose enough to rattle or buzz.
CORRECTIVE ACTION
Replace the warm-up TWC heat shield, and install a splash shield cover.
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PARTS INFORMATION
WARRANTY CLAIM INFORMATION
Failed Part: P/N 18120-RCA-A00
Defect Code: 00801
Symptom Code: 04216
Skill Level: Repair Technician
REPAIR PROCEDURE
1. Remove the engine cover.
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2. 2010-11 MDX only: Remove the No.5 ignition coil and the heat insulator.
3. Disconnect the front (Bank 2) A/F Sensor 6P and secondary HO2S 4P connectors.
4. 2010~11 MDX only: Remove the EGR pipe upper mounting bolts.
5. Place a piece of cardboard or some other barrier between the front of the warm-up TWC and the radiator to protect the radiator from damage.
6. Raise the vehicle.
7. Remove the lower front splash shield.
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8. 2010-11 MDX only: Remove the EGR pipe lower mounting nuts.
9. 2010-11 MDX only: Remove the EGR pipe.
10. Remove the two lower heat shield bolts.
NOTE:
If the bolts are severely corroded, remove them using best shop practices. Do not use an air chisel as this may cause internal damage to the
warm-up TWC, the A/F sensor, or the secondary HO2S.
11. Remove the two upper heat shield bolts, and remove the front half of the heat shield.
12. Remove the nuts that attach the A-pipe to the front and rear warm-up TWCs and allow the pipe to hang from its hanger.
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13. Remove the four nuts that attach the front warm-up TWC to the cylinder head.
14. Carefully slide the warm-up TWC off the studs and remove the rear half of the heat shield.
NOTE:
Do not try to remove the warm-up TWC
from the vehicle because there is not enough room.
15. Install the new front and rear halves of the heat shield onto the warm-up TWC and leave the bolts finger tight.
NOTE:
2010-11 MDX only: The two bolts with a large washer go in the top holes.
16. Install the front warm-up TWC onto the cylinder head using a new gasket and new nuts. Tighten the nuts in a crisscross pattern in two or three
steps to 31 N.m (23 lb-ft).
17. Torque the heat shield bolts to 12 N.m (8.7 lb-ft).
18. Install the A-pipe to the warm-up TWCs using new gaskets and nuts. Tighten the nuts to 54 N.m (40 lb-ft).
19. 2010-11 MDX only: Install the EGR pipe using new gaskets. Torque the lower nuts to 22 N.m (16 lb-ft), and leave the upper bolts finger tight.
20. Reinstall the lower front splash shield.
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21. Install the splash shield cover into the splash shield below the radiator drain.
22. Lower the vehicle.
23. 2010-11 MDX only: Torque the EGR pipe upper mounting bolts to 22 N.m (16 lb-ft).
24. Remove the cardboard from between the front of the warm-up TWC and the radiator.
25. Reconnect the front (Bank 2) A/F sensor 6P and secondary HO2S 4P connectors.
26. 2010-11 MDX only: Reinstall the No.5 ignition coil and heat insulator. Torque the ignition coil mounting nut and heat insulator mounting nuts
to 12 N.m (8.7 lb-ft).
27. Reinstall the engine cover.
