Fuel - Carburetor Throttle Plate Freezes
Number: 85-174Section: 6C
Date: JAN., 1986
Subject: CARBURETOR THROTTLE PLATE FREEZES
Model and Year: 1985 SPECTRUM
TO: ALL CHEVROLET DEALERS
Some 1985 Spectrum cars may exhibit an occasional no start condition due to ice forming on the throttle plate shaft in the carburetor. This condition is due to the ingress of snow into the underhood area and hence into the carburetor air intake system during driving in snowy conditions. This results in subsequent melting and refreezing of residual snow in the throttle plate and shaft area of the carburetor when the vehicle is parked, engine off, for a period of time (typically overnight) under freezing conditions. When a restart is then attempted, setting the choke causes the throttle plate to open and stick in the open condition due to the resistance of the ice overcoming the throttle return spring effort. This results in a no start condition.
AIR-DUCT INLET:
Subject vehicles can be corrected by installing duct-air inlet, P/N 94408584, reference illustration 1, along with R/LH dust covers adjacent to the steering tie-rod holes. Reference illustration 2 for part numbers.
The following procedures should be used:
INSTALLATION OF NEW DUCT-AIR INLET.
1. Loosen clamping bolt at duct to air cleaner.
2. Remove clamping nut from hold down strap between duct and front end panel.
3. Remove duct-air inlet.
4. Install a new duct-air inlet by reversing steps 1-3.
DUST COVER INSTALLATION:
DUST COVERS:
INSTALLATION OF DUST COVERS - SEE ILLUSTRATION 2 and 3.
1. Locate LH dust cover (shown in illustration 2, identified by approximately 1 inch square cut-out at lower, front, inboard corner) such that the two (2) holes in the cover are aligned with the two (2) existing holes in the sheet metal adjacent to the tie rod aperture.
2. With center stem of clip extended, not pressed fully into clip, insert clips into holes in dust cover flange.
3. Press center stem of clip towards dust cover flange until head of stem is seated in body of clip. Ensure that cover is firmly attached.
4. Following steps 1-3 similarly install the RH dust cover.
Labor Operation Number: T1144
Labor Time : .4 hours