Engine - Stalls When Starting or Cold Hesitation and Sag

87chevy18
Number: 86-248

Section: 6E

Date: September, 1987
Subject: ENGINE DRIVEABILITY - COLD HESITATION AND SAG


Model and Year: 1986 SPECTRUM
TO: ALL CHEVROLET DEALERS


Some 1986 Spectrum vehicles may experience engine driveability complaints of "stalls when starting" or hesitation and sag when driving with the engine at cold operating temperatures.

For vehicles exhibiting these conditions a new PROM and a cold timing advance kit have been developed and are available from GMSPO by ordering the following Part Numbers:

ALL VEHICLES: KIT - COLD TIMING ADVANCE P/N 94479402

(Kit includes the following components)
Vacuum Switching Valve (VSV) P/N 94440223
Hose P/N 94006697
Clip P/N 94025647
Label P/N 94473176
Harness P/N 94458535
Valve P/N 94249018
Hose P/N 94440224

AUTO. TRANS. VEHICLES: Calibrator (PROM) PIN 16069045

MAN. TRANS. VEHICLES: Calibrator (PROM) PIN 16069048

FIGURE 1 - WITHOUT A/C:

FIGURE 2 - WITH A/C:

SERVICE PROCEDURE:

1. Install the calibrator appropriate to the transmission installed in the vehicle using normal service procedures. Reference Figure 1 or Figure 2 as appropriatewithout A/C with A/C.

2. Attach cold timing advance kit VSV bracket (P/N 94440223) to left hand strut tower at existing threaded hole using bolt supplied.

3. Disconnect vacuum hose - inlet manifold to distributor vacuum advance servo - discard hose.

4. Connect vacuum hose, part of P/N 94440224, shown shaded in Figure 1 and 2 to inlet manifold connection, VSV and delay valve (P/N 94249018) as shown on vacuum hose routing label, P/N 944731756.

5. Connect vacuum hose, part of P/N 94440224, shown white in Figure 1 and 2 to distributor vacuum advance servo and VSV as shown on vacuum hose routing label.

FIGURE 3:

6. Disconnect EFE heater harness connector located at rear right hand side of engine adjacent to alternator - See Figure 3.

FIGURE 1 - WITHOUT A/C:

FIGURE 2 - WITH A/C:

7. Connect electrical harness VSV, P/N 94458535, to EFE harness connector (part of cold timing advance kit) to EFE heater harness connector as shown in Figure 1 and
2. Route and secure harness to existing clips at dashupper panel.
Labor Operation Number: T1253

Labor Time: .6 Hours