Beretta L4-121 2.0L (1987)
Idle Speed: All Technical Service Bulletins
Engine - Base Idle RPM Setting
Number:
88-239-6E
Section:
6E
Date:
JUNE, 1988
Subject:
SERVICE MANUAL UPDATE -
BASE IDLE RPM SETTING
Model and Year: 1987-88 CAVALIER, CORSICA, BERETTA
WITH 2.0L (VIN CODE 1) ENGINE
TO:
ALL CHEVROLET DEALERS
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
1987
1988
450 - 650
450 - 650
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.
