Engine Idle - Base RPM Setting
88pontiac07Bulletin Number: 88-6-47
Reference Number: 836521
Publish Date: 5/88
Subject: BASE IDLE RPM SETTING
Models 1987-88 SUNBIRD WITH OHC-4
Affected: ENGINE (VIN CODE K)
The "minimum idle speed adjustment" in the Service Manual, Section 6E2-C2 specifies an idle setting that is too tightly held. "Minimum idle RPM" will depend upon miles on the engine, altitude, accessory load, etc., thus implying a broader acceptable range than currently specified. This factory set air gap clearance (throttle blade-to-bore) should not require any resetting UNLESS the TBI's throttle body is replaced. If the throttle body is replaced, then the following wider setting band should be used with the setting procedure specified in Section 6E2-C2.
Hot Idle
OHC-4 Engine 1987 1988
VIN K 450 - 600 450 - 600
NOTICE: ONCE THE IDLE AIR CONTROL (IAC) MOTOR IS RECONNECTED, A
HIGHER ECM CONTROLLED IDLE RPM OVERRIDES THE BASE "MINIMUM
IDLE SPEED" VIA THE IAC CONTROLLED AIR PATH INTO THE INTAKE
MANIFOLD.
THE IAC's PROPER COUNT POSITION SHOULD BE CHECKED, REFER TO
CHART C-2C, AND IF NECESSARY RESET THE IAC VALVE POSITION
BY DRIVING THE VEHICLE AT ITS "RESET SPEED" (45 MPH) AS
STATED IN SECTION 6E2-2C.
Use applicable labor time and operation number.