Emissions - Rough Idle Just After Warm Restart
Category 4Applicable Model/s 626 TURBO
Subject
EMISSION CONTROL UNIT
Bulletin No. 022/86
Issued 12/18/86
Revised
DESCRIPTION
Fuel tends to vaporize in the distribution pipe due to high under hood temperatures. This vaporizing of the fuel will cause rough engine idle just after warm re-start.
Emission Control Unit:
VIN OF PRODUCTION CHANGE:
To eliminate this problem, the emission control unit has been modified to allow higher fuel pressure at lower temperatures. This will help prevent fuel vaporization in the fuel distribution pipe and reduce rough idle just after warm re-start.
The intake air temperature operating range for the 3-way solenoid valve has been changed from 131~F to 50~F.
During the first 2 minutes after the engine is re-started, vacuum is cut to the pressure regulator and the fuel pressure is increased under the following conditions.
^ Before Modification:
Coolant temperature is above 158~F and intake air temperature is above 131~F.
^ After Modification:
Coolant temperature is above 158~F and intake air temperature is above 50~F.
PARTS INFORMATION
PART NUMBER
DESCRIPTION INTERCHANGEABILITY
NEW OLD
FEH5 18 880C FEH5 18 880B Emission Control Unit NEW --> OLD