Legend Coupe V6-3206cc 3.2L SOHC FI (1991)
Vacuum Harness HVAC: All Technical Service Bulletins
Emissions Control - Buzzing Noise (A/T)
YEAR
1991 - 92
MODEL
LEGEND
with A/T
VIN APPLICATION
See VEHICLES AFFECTED
June 1, 1992
BULLETIN NO.
92-021
Buzzing Noise From the Emissions Control Box
PROBLEM
A buzzing/humming noise can be heard when accelerating or climbing a hill at engine speeds between 2,000 and 3,000 rpm.
NOTE:
The noise is loudest when the manifold vacuum is between 50 and 100 mm Hg.
VEHICLES AFFECTED
1991 Coupe - ALL
1992 Coupe - Thru VIN JH4KA82 . . . NC002517
1991 Sedan - ALL
1992 Sedan - Thru VIN JH4KA76 . . . NC021685
DIAGNOSIS
Pinch off the # 5 vacuum hose at the control box, and test drive the car. If the buzzing noise goes away, replace the constant vacuum control (CVC)
valve.
NOTE:
Pinching off the # 5 hose disables the CVC valve, causing the check engine light to flash a code 12. To clear the code and reset the ECU, remove the #
15 AGC (7.5A) fuse from the under-dash fuse box. Leave the fuse out for approximately 10 seconds, then reinstall the fuse.
CORRECTIVE ACTION
Replace the CVC valve with the part listed under PARTS INFORMATION.
1.
Remove the control box cover by depressing the lock tabs on each side of the cover.
2.
Remove the CVC valve mounting screw, then turn the valve over to remove the two vacuum hoses.
