S10/T10 Blazer 2WD L4-121 2.0L VIN Y 2-bbl (1983)
EGR Valve: Technical Service Bulletins
Emissions - Rough Idle or Coolant Loss
Number:
83-128
Section:
6 (VI)
Date:
Feb.., 1984
Subject:
ROUGH IDLE AND/OR COOLANT LOSS WITH 2.0L LQ2 ENGINE
Model and Year: 1983 "S/T" TRUCK
TO:
ALL CHEVROLET DEALERS
Some 1983 "S/T" trucks with 2.0L LQ2 engines may exhibit poor or rough idle, and/or coolant loss. This condition may be caused by
a warped EGR valve adaptor (aluminum). Warpage in this area can result in some of the following conditions.
1.
Leakage across the base of the EGR valve.
2.
Leakage at the base of the EGR valve to atmosphere.
3.
Leakage of coolant from head to EGR valve inlet or outlet.
4.
Leakage of coolant to outside of head.
Conditions #1 and #2 generally result in rough idle. Conditions #3 and #4 can be detected by a coolant loss.
Replacement with P/N 14077282 (adaptor - cast iron) and P/N 14028962 (stud - 2 needed, torque to 40 N-m) will correct these
conditions.
Use applicable labor operation.