EL Camino V6-229 3.8L VIN 9 (1984)
Engine - Momentary Hunting at Idle on Deceleration
Number:
83-T-83
Section:
6A (VI)
Date:
April, 1984
Subject:
IDLE SHAKE ON 3.8L (LC3) -
VIN CODE 9 ENGINES
Model and Year: 1982-83 MALIBU AND 1982-84
MONTE CARLO, EL CAMINO, IMPALA AND CAPRICE
TO:
ALL CHEVROLET DEALERS
This cancels and supercedes Bulletin 83-T-83 dated September, 1983. This issue adds 1984 Impala and Caprice and clarifies by
model and year, momentary hunting at idle and excessive idle shake.
MOMENTARY HUNTING AT IDLE (1982-83 MALIBU, 1982-84 MONTE CARLO AND EL CAMINO)
It is possible to encounter a momentary "hunting" at idle on deceleration brake stops. This condition can be minimized by setting the
base idle (ISC retracted) to 500 RPM (released spec. was 475). Refer to 1983 Shop Manual, E2ME, Carb. 6C2-5, Idle Speed
Adjustment, Items 9-11 for the procedure to make this adjustment.
EXCESSIVE IDLE SHAKE (ALL MODELS LISTED)
A harsh shake may occur at normal idle conditions, A/C on or off. This condition may be caused by grounded engine mounts which
can be corrected by installing a shim, P/N 14082881, between the L.H. engine mount and the block and using three (3) longer bolts,
P/N 435611. If the drive idle shake is improved, but not to an acceptable level, 6 mm of shims should also be installed between the
R.H. mount and the block.
Technical Service Bulletin # 8497
Date: 840401
A/T - 3-2 and/or 2-1 Coastdown Clunk
Number:
84-97
Section:
7A (VIIc)
Date:
April, 1984
Subject:
3-2 AND/OR 2-1 COASTDOWN CLUNK ON VEHICLES WITH THM 200C TRANSMISSIONS
Model and Year: 1983 CAMARO AND ALL 1984 VEHICLES WITH THM 200C TRANSMISSIONS
TO:
ALL CHEVROLET DEALERS
Some 1983 and 1984 THM 200C model transmissions may experience a 3-2 and/or 2-1 coastdown clunk condition. This condition is
most noticeable during the 3-2 downshift at approximately 18-20 miles per hour.
When servicing any 1983 or 1984 THM 200C model transmission for 3-2 and/or 2-1 coastdown clunk, refer to the service procedure
below.
SERVICE PROCEDURE
1.
Check engine idle speed. This coastdown clunk is especially noticeable when the engine is cold.
2.
Check rear differential back lash, correct if necessary.
3.
If this coastdown clunk condition still exists, after checking the above stated service procedure on 1983 CN, CS, and HO models
equipped with 2.8L V6 engines, replace the valve body spacer plate with P/N 8648303. On car service can be performed in
changing the valve body spacer plate, refer to your service manual for proper installation procedure.
