Cooling System - Booming Noise Heard At 2,000 RPM
GROUP ENGINENUMBER 052 [REVISED]
MODEL BORREGO (HM)
DATE APRIL 2010
SUBJECT:
2009 MY THERMOSTAT HOUSING ASSEMBLY REPLACEMENT (3.8L ENGINE)
This bulletin provides information relating to a running change made on Borrego (HM) vehicles equipped with 3.8L engines produced from 5/20/2008 - 10/8/2008 which may experience a booming type noise while driving around 2000 rpm. The booming noise is transmitted into the inside of the vehicle via the heater pipes and the thermostat housing. Follow this service procedure as directed to repair this customer concern.
NOTICE
Changes between this revised Technical Service Bulletin and the original version are shown with a black bar and/or asterisks.
PARTS INFORMATION
1. Remove the intake manifold using the electronic service information, drain coolant as required.
2. Cover the air inlets to prevent to avoid foreign materials from entering the lower intake manifold. Disconnect fuel line and reposition out of the way.
NOTICE
Take care to avoid foreign materials from entering the engine during work procedure.
3. Disconnect heater hoses from heater pipes and nipples of the thermostat housing assembly.
4. Remove bolt for the auto transaxle oil level dipstick tube if necessary.
5. Remove the engine coolant pipe from the thermostat housing.
6. Partially remove the wiring harness for clearance which passes over the thermostat housing assembly.
7. Remove the 6 thermostat housing assembly mounting bolts from the engine.
8. Remove the thermostat housing assembly from the vehicle.
9. Install the new wiring harness connector bracket to the new thermostat housing assembly. Then, install the new thermostat housing assembly and gaskets to the vehicle in reverse order of removal.
Torque the six (6) fasteners to 14-17 ft. lbs (19-23 Nm).
10. Cut off and discard the WTS (Water Temperature Sensor) wiring harness side connector.
Connect wires in the same color following the procedures below. For Pin 180, cut wire, then seal the cut end by using a heat shrink tube supplied in the kit. Pin 180 is not being used.
11. Twist and join the wires of current and new WTS harness connector and splice terminals supplied in the kit, then solder the connections.
12. Cover the wire joints with heat shrink tubes and subject heat shrink tubes to heat. Tape the wires with electrical tape as required.
13. *Replace the noise condenser wiring harness side connector with new one supplied in the kit.
^ Connect 127 to 127
^ Terminate 128; then cut and seal exposed wire end
Install all the removed components in reverse order of removal. Road test the vehicle to ensure proper operation*
AFFECTED PRODUCTION RANGE:
Borrego (HM) production from 5/20/2008 through 10/8/2008.
WARRANTY INFORMATION