S10/T10 P/U 4WD L4-151 2.5L (1985)
PROM - Programmable Read Only Memory: Technical Service Bulletins
Vehicle - Excessive Hydrocarbon Exhaust Emission
Number:
86-233
Section:
6E
Date:
April, 1987
SUBJECT:
STATE EMISSION TESTING INSPECTION MAINTENANCE
MODELS:
1985-86 S/T TRUCKS AND M VANS WITH THE 2.5L L4 ENGINE (VIN CODE E) AND
MANUAL TRANSMISSION
Some 1985-86 S/T trucks or M vans with 2.5L engines and manual transmissions may experience difficulty meeting the hydrocarbon (HC) exhaust
emission requirements of state inspection maintenance test programs. If this condition cannot be corrected using the service procedures in Section
6E-Engine Emissions of the appropriate service manual, the following service PROMs are available from GMSPO to repair the condition. Use the
PROM replacement procedure in Section 6E-Engine Emissions for PROM replacement.
Service
Rear
PROM
Model
Engine
Transmission
Axle
Tire Size
1228389
M Van
2.5L (LN8)
4-Spd Man (MR2)
3.42 (GU6)
All
1228390
M Van
2.5L (LN8)
4-Spd Man (MR2)
3.73 (GT4)
All
1228391
M Van
2.5L (LN8)
4-Spd Man (MR2)
4.10 (GT5)
All
1228392
M Van
2.5L (LN8)
5-Spd Man (ML3)
3.73 (GT4)
All
1228393
M Van
2.5L (LN8)
5-Spd Man (ML3)
4.10 (GT5)
All
1228381
S Pickup/
2.5L (LN8)
4-Spd Man (M73)
3.73 (GT4)
All
Extended Cab
1228385
S Blazer/
2.5L (LN8)
4-Spd Man (M73)
3.73 (GT4)
All
T (All)
2.5L (LN8)
4-Spd Man (MC9)
3.73 (GT4)
All
4-Spd Man (M73)
4.11 (HO4)
P235/75R15
1228386
S Blazer/
2.5L (LN8)
4-Spd Man (MC9)
4.11 (HO4)
All
T (All)
2.5L (LN8)
4-Spd Man (MC9)
4.11 (HO4)
All
4-Spd Man (M73)
4.11 (HO4)
All Tires Except
P235/75R15
1228382
S Longbed
2.5L (LN8)
4-Spd Man (M73)
4.11 (HO4)
All
Pickup
1228383
S (All)
2.5L (LN8)
5-Spd Man (ML3)
3.73 (GT4)
All
1228384
S Pickup/
2.5L (LN8)
5-Spd Man (ML3)
4.11
(HO4)
All
Extended Cab
1228388
T (All)
2.5L (LN8)
5-Spd Man (ML2)
4.11 (HO4)
P235/75R15
1228387
S Blazer/
2.5L (LN8)
5-Spd Man (ML3)
4.11 (HO4)
All
1228353
S (All)
2.5L (LN8)
4-Spd Man (M73)
3.42 (GU6)
All
The following codes identify specific transmissions.
NOTICE:
Borg Warner transmissions used in S/T trucks can be identified by the separate bell housing to transmission. Isuzu transmissions are a
complete assembly.