Colt L4-1597cc 1.6L SOHC Turbo (1985)
Clutch Control Valve: All Technical Service Bulletins
A/T - Warm Surge At Steady Speeds
Models
1985-1987 LA (Colt) & NF45Z (Colt Vista) Vehicles Equipped With a KM 171 or 172 Automatic Transaxle
Subject
Warm Surge at Steady Speeds
Index
DRIVEABILITY
Date
March 23, 1987
No..
18-08-87 (C2-18)
P-990
SYMPTOM/CONDITION
Engine may surge at full operating temperature with the vehicle at steady cruise/light load condition.
DIAGNOSIS
If a surge from 100 to 200 rpm can be felt when the engine speed is between 1800 and 2600 rpm, disconnect the automatic transmission control unit. If
the surge is gone, proceed with the following repair procedure.
PARTS REQUIRED
Transmission Modification Package PN MD728159
Consists of:
1
Damper Clutch Control Valve
PN MD727246
1
Damper Clutch Control Sleeve
PN MD723456
1
Lower Valve Body
PN MD727244
1
Lower Valve Spring
PN MD725203
1
Solenoid Valve
PN MD727245
1
Gasket, Oil Pan
PN MD707183
2
O-Ring
PN MD707603
1
O-Ring
PN MD707752
REPAIR PROCEDURE
This procedure involves replacing the transmission lower valve body damper clutch control valve, sleeve, and spring, and the lock-up solenoid valve.
This will correct a lock-up transmission induced engine surge.
