For 1990-2009 cars

# PROM CALIBRATION/REPLACEMENT UPDATED DIAGNOSTICS

#### MODELS AFFECTED: 1980-1989 BROUGHAMS, ELDORADOS, AND SEVILLES 1982-1988 CIMARRONS 1985-1989 DE VILLES AND FLEETWOODS 1987-1989 ALLANTES

This bulletin replaces bulletins T-87-18A and T-87-18, Group 6E, which should be discarded.

These charts summarize all 1980 through 1989 C, D, E, K, V, and J gasoline engine PROM calibrations to date. When any diagnosis leads to PROM replacement, the service PROM part number listed should be used. Should any additional PROM calibration changes be made, the GMSPO parts distribution system will automatically supersede these service part numbers.

PROM changes may be made for many different reasons. For instance, a calibration change may be made in conjunction with component changes, for a repair relative to a current field condition, or as a running change to provide minor modifications affecting driveability or fuel economy. Therefore, if a PROM I.D. is lower than the latest PROM available, it does not necessarily need replacement. Refer to the bulletin listed for details about the symptom that may require a PROM change.

1980 E/K EQUIPPED WITH 6.0L DEFI V-8 ENGINE DEFI - FEDERAL EMISSIONS* ------------------------ Production Service ECM Service ECM Broadcast Code Broadcast Code Part Number -------------- --------------- ----------- Gen. 1: AC CJ 1224539 Gen. 2: AD CJ 1224539 Gen. 3: CJ CJ 1224539

* NOTE: The PROM is not replaceable separately on 1980 DEFI vehicles. A PROM is included in 1980 DEFI service ECM's.

1980 C EQUIPPED WITH 6.0L C-4 V-8 ENGINE AND CALIFORNIA EMISSIONS 1980 LIMOUSINE EQUIPPED WITH 6.0L C-4 V-8 ENGINE 1980-1984 COMMERCIAL CHASSIS EQUIPPED WITH 6.0L C-4 V-8 ENGINE

Service Broadcast PROM Service PROM P/N Code Part I.D. -------- ---- --------- 1224674 AF 1359

1981 C, D, E, AND K EQUIPPED WITH 6.0L MD-DFI V-8-6-4 ENGINE 1981-1984 LIMOUSINES EQUIPPED WITH 6.0L MD-DFI V-8-6-4 ENGINE

First Gen. PROM'S:

VIN ECM PROM Service Service Broadcast# Service P/N Part I.D. PROM P/N ----------- ------------ ---------- --------- C Fed. 100001-130880 1224760 #1-7948FS 1225772 #2-7949FS

C C al. 100001-143985 1224760 #1-6965LW 1225772 #2-6967LW

E/K Fed. E 600001-616866 1224760 #1-2068BH 1225866 K 680001-690461 #2-2933BH

E/K Cal. E 600001-617927 1224760 #1-7013KB 1225773 K 680001-691350 #2-7014KB

D Fed. 100001-130880 1225120 #1-7087LY 1225125 #2-7088LY

C Fed. After 130880 1225120 #1-7069KD 1225775 #2-707OKD

C C al. After 143985 1225120 #1-7085KK 1225775 #2-7086KK

C E xp. 1225120 #1-7077KH 1225127 #2-7078KH

E/K Fed. E After 616866 1225120 #1-7067KC 1225774 K After 690461 #2-7068KC

E/K Cal. E After 617927 1225120 #1-7079KJ 1225774 K After 691350 #2-708OKJ

E/K Exp. 1225120 #1-7075KF 1225126 #2-7076KF

D Fed. After 130880 1225120 #1-005OAAF 1225298 #2-0051AAF

1981 PROM I.D.'s are on a sticker on top of the PROM.

1981 C, D, E, AND K EQUIPPED WITH 6.0L MD-DFI V-8-6-4 ENGINE (BULLETIN I-83-49) 1981-1984 LIMOUSINES EQUIPPED WITH 6.0L MD-DFI V-8-6-4 ENGINE ------------------------------------------------------------- Second Gen. PROM's: Bulletin T-83-49 "Cold Driveability"

VIN ECM PROM Service Service Broadcast # Service P/N Part I.D. PROM P/N ----------- ----------- ---------- -------- C Fed. 100001-130880 1224760 #1-5785LW 1225772 #2-5786LW C C al. 100001-143985 1224760 #1-5785LW 1225772 #2-5786LW E/K Fed. E 600001-616866 1224760 #1-5869BH 1225866 K 680001-690461 #2-5884BH E/K Cal. E 600001-617927 1224760 #1-5779KB 1225773 K 680001-691350 #2-5778KB D Fed. 100001-130880 1225120 #1-7087LY 1225125 #2-7088LY C Fed. After 130880 1225120 #1-586OKK 1225775 #2-5861KK C Cal. After 143985 1225120 #1-586OKK 1225775 #2-5861KK E/K Fed. E After 616866 1225120 #1-5853KJ 1225774 K After 690461 #2-5854KJ

E/K Cal. E After 617927 1225120 #1-5853KJ 1225774 K After 691350 #2-5854KJ D Fed. After 130880 1225120 #1-005OAAF 1225298 #2-0051AAF

1981 PROM I.D.'s are on a sticker on top of the PROM.

1981, C, E, AND K EQUIPPED WITH 4.1L V-6 CCC SERVICE ECM P/N 1224810 ----------------------- Production Service ECM PROM Service Service ECM Broadcast Code Broadcast Code Part I.D. Part Number First Gen.: -------------- -------------- --------- ----------- --------- C DW ACF 1563 1225325 E/K DX-Version 1 DX-Version 2* 5994 1226079 C Cal. LN ACH 1564 1225326 E/K Cal. LM LM 6638 1224839

#### Second GEN:

C ACF ACF 1563 1225325 C Cal. ACH ACH 1564 1225326 E/K DX-Version 2* DX-Version 2* 5994 1226079

* Retrofit - P/N 1226079 to reduce detonation.

PROM I.D.'s are on a sticker on top of the PROM.

1982 C, E, AND K EQUIPPED WITH 4.1L DFI V-8 ENGINE (BULLETIN I-82-74) SERVICE ECM P/N 1225650 ------------------------ Production Service Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number ----------- ------------ ----------- First Gen.: ------------ C Fed. WA (10) AUO (11) 1225981 C Cal. WB (20) AUP (21) 1225983 C Export WC (36) WC (30) 1225655 C Alt. WB (20) AUP (21) 1225983 E/K Fed. WD (40) AUR (41) 1225984 E/K Cal. WF (50) AUS (51) 1225979 E/K Export WH (60) WH (60) 1225657 E/K Alt. WF (50) AUS 1225979 E/K Fed. Dig.* AAH(70) AUT 1225980 E/K Cal. Dig.* AAJ(80) AUU 1225982 E/K Export Dig.* AAK(90) AAK (90) 1225659 E/K Alt. Dig.* AHN(180) AHN (180) 1225667

Second Gen.: Bulletin I-82-74 Raises TCC Engagement Speed ------------ C Fed. AUO (11) AUO (11) 1225981 C Cal. AUP (21) AUP (21) 1225983 C Alt. AHL (120) AHL (120) 1226038 E/K Fed. AUR (41) AUR (41) 1225984 E/K Cal. AUS (51) AUS (51) 1225979 E/K Alt. AHM (150) AHM (150) 1225666 E/K Fed. Dig.* AUT (71) AUT (71) 1225980 E/K Cal. Dig.* AUU (81) AUU (81) 1225982 E/K Alt. Dig.* AHN (180) AHN (180) 1225667

* Dig. = Digital Instrument Cluster

PROM I.D. is ECM data parameter .1.3

#### NOTE: 1982 service PROM part number package contains two PROM's.

1982 C, E, AND K EQUIPPED WITH 4.1L CLCC V-6 ENGINE SERVICE ECM P/N 1225500 ------------------------ Production Service Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number -------------- -------------- --------- ----------- First Gen.: ---------- C Fed. NA ART 5333 1225909 C Cal. NB ARU 5327 1225910 E/KFed. ND ASU 9860 1225976 E/K Cal. NF ASX 5593 1225977 E/K Export AUY AUY 6422 1225978

Second Gen.: ------------- C Fed. ART ART 5333 1225909 C Cal. ARU ARU 5327 1225910 E/KFed. ASU ASU 9860 1225976 E/KCal. ASX ASX 5593 1225977

PROM I.D.'s are on a sticker on top of the PROM.

1982 J EQUIPPED WITH 1.8L CCC L-4 ENGINE SERVICE ECM PN 1225500 ---------------------- Production Service Service Service Begin End Broadcast Broadcast PROM PROM B.P. B.P. Code Code Part I.D. P/N First Gen.: ---- ---- ---- ---- --------- --- ---------- Fed. Auto. 400001 416172 AMM AMM 3425 1226055 416173 421979 BKY BKW 7654 1226047 421980 432258 BKW BKW 7654 1226047 Cal. Auto. 400001 416172 AMM AMM 3425 1226057 416173 432258 BKY BKY 7665 1226049 All Manual 400001 416172 AML AML 1376 1226721 416173 423220 ADN ADN 1464 1225753 423221 432258 AWB AWB 1336 1225751

Second Gen.: Bulletin T-84-49 "False Code 34 Set During Sustained Idle or Low ----------- Speed Deceleration".

Fed. Auto. 400001 416172 AMM AMM 3425 1226055 416173 421979 BKW BKW 7654 1226047 421980 432258 BKW BKW 7654 1226047 Cal. Auto. 400001 416172 AMM AMM 3425 1226057 416173 432258 BKY BKY 7665 1226049 All Manual 400001 416172 AML AML 1376 1226721 416173 423220 ADN ADN 1464 1225753 423221 432258 AWB AWB 1336 1225751

PROM I.D.'s are on a sticker on top of the PROM.

1983 C, E, AND K EQUIPPED WITH 4.1L DFI V-8 ENGINE SERVICE ECM P/N 1226028 OR P/N 1226930 (SEE BULLETIN 84-84, GROUP 6C) --------------------------------------------------------------------- Production Service Broadeast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number ------------ ------------ ----------- First Gen.: ----------- C Fed. AFY (12) CTK (14) 1226529* C Cal. AFZ (22) CTL (24) 1226530* C Export AHA (31) CTM (33) 1226531 C Alt. AXK (121) CTW (123) 1226538 E/K Fed. AHB (42) CTN (44) 1226532* E/K Cal. AHC (52) CTP (54) 1226533* E/K Export AHD (61) CTR (63) 1226534 E/K Alt. AXL (151) CTX (153) 1226539 E/K Fed. Dig. AHF (72) CTS (74) 1226535* E/K Cal. Dig. AHH (82) CTT (84) 1226536* E/K Export Dig. AHJ (91) CTU (93) 1226537 E/K Alt. Dig. AXM (181) CTY (183) 1226540

Second Gen.: ------------ C Fed. CCD (13) CTK (14) 1226529* C Cal. CCF (23) CTL (24) 1226530 C Alt. CCR (122) CTW (123) 1226538 E/K Fed. CCK (43) CTN (44) 1226532* E/K Cal. CCK (53) CTP (54) 1226533* E/KAlt. CCS (152) CTX (153) 1226539 E/K Fed. Dig. CCM (73) CTS (74) 1226535* E/K Cal. Dig. CCN (83) CTT (84) 1226536* E/K Alt. Dig. CCT (182) CTY (183) 1226540

Third Gen.: Bulletin T-83-94 "Idle Speed Varies with A/C Clutch Engagement". ---------- C Fed. CTK (14) CTK (14) 1226529* C Cal. CTL (24) CTL (24) 1226530* C Export CTM (33) CTM (33) 1226531 C Alt. CTW (123) CTW (123) 1226538 E/K Fed. CTN (44) CTN (44) 1226532* E/K Cal. CTP (54) CTP (54) 1226533* E/K Export CTR (63) CTR (63) 1226534 E/K Alt. CTX (153) CTX (153) 1226539 E/K Fed. Dig. CTS (74) CTS (74) 1226535* E/K Cal. Dig. CTT (84) CTT (84) 1226536* E/K Export Dig. CTU (93) CTU (93) 1226537 E/K Alt. Dig. CTY (183) CTY (183) 1226540

* For 52-60 mph surge complaint use Fourth Gen. P/N-Serviceman Bulletin 84-55A.

PROM I.D. is ECM data parameter .1.3

1983 C, E, AND K EQUIPPED WITH 4.1L DFI V-8 ENGINE -------------------------------------------------- Production Service Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number ------------ ------------ ----------- Fourth Gen.: Bulletin T-84-55A "52-60 mph Surge or Chuggle". ----------- C Fed. PROM's only CTK (100) 1227321** C Cal. available as CTL (26) 1226834** E/K Fed. retrofit CTN (132) 1227157** E/K Cal. CTP (57) 1226835** E/K Fed. Dig. CTS (162) 1227158** E/K Cal. Dig. CTT (87) 1226836**

** These PROM's to be applied only to correct 52-60 mph surge or chuggle. See Third Gen. for regular service replacement. Before applying the PROM, see Serviceman Bulletin T-84-55A for specific diagnostic steps that must be performed.

PROM I.D. is ECM data parameter .1.3

1983 J EQUIPPED WITH 2.0L EFI L-4 ENGINE SERVICE ECM P/N 1226026 ----------------------- Service Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number -------------- -------------- --------- ----------- First Gen.: ------------- Fed. Auto. BAJ CDT-Version 2 6472 1226472 Fed. Manual AMR CDU 3962 1226473 Cal. Auto. BAH CDZ-Version 2 0236 1226985 Cal. Manual BAA CFA 3986 1226477

Second Gen.: Bulletin T-83-67 "Engine Detonation"* ------------ Fed. Auto. CDT-Version 1 CDT-Version 2 2178 1226789** Fed. Manual CDU CDU 3962 1226473 Cal. Auto. CDZ-Version 1 CDZ-Version 2 0236 1226985** Cal. Manual CFA CFA 3986 1226477

Third Gen.: Bulletin T-84-50 "Spark Knock or Detonation"*** ----------- Fed. Auto. PROM's available CDT-Version 2 2178 1226789 Cal. Auto. only as retrofit CDZ-Version 2 0236 1226985

Fourth Gen.: Special Policy Adjustment Bulletin 84-P-1 reissue**** ------------ Fed. Auto. PROM's available CDT-Version 3 4128 1227254 only as retrofit

* For detonation - running production change at B.C. 410423.

* * CDT and CDZ Version 1 PROM's (Bulletin T-83-67) were superseded by CDT and CDZ Version 2 PROM's (see Bulletin T-84-50).

* * * Retrofit for detonation only - for regular service replacement use First Gen.

**** Retrofit for cold startability only (see Bulletin 84-P-1 reissue).

PROM I.D.'s are on a sticker on top of the PROM.

1984 D, E, AND K EQUIPPED WrrH 4.1L DFI V-8 ENGINE SERVICE ECM P/N 1226028 OR 1226930 (SEE BULLETIN 84-84) -------------------------------------------------------- Production Service Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number First Gen.: ------------ ----------- ----------- ------------ D Fed. CAN (15) DMW (16) 16042063 D Cal. DBB (25) DRD (27) 16042787 D Export DBC (35) DMK (35) 16042036 D Opt. Axle DBN (124) DMU (124) 16042060 E/K Fed. CAT (45) DMY (47) 16042069** E/K Cal. DBF (55) DMM (55) 16042042 E/K Export DBJ (65) DMP (65) 16042048 E/K & E Conv. CAX (154) DLZ (154) 16042010 Opt. Axle E Fed. Conv. CYP (46) DMA (46) 16042014 E Cal. Conv. CYS (56) DMC (56) 16042020 E/K Fed. Dig. CAO (75) DMX (77) 16042066** E/K Cal. Dig. DBH (85) DMN (85) 16042045 E/K Export Dig. DBK (95) DMR (95) 16042051 E/K & E Conv. CAS (184) DLW (184) 16042000 Opt. Axle Dig. E Fed. Conv. Dig. CYR (76) DMB (76) 16042017 E Cal. Conv. Dig. CYT (86) DMD (86) 16042024

Second Gen.: ------------- D Fed. DCM (16) DMW (16) 16042063 E/K Fed. DCP (47) DMY (47) 16042069** E/K Fed. Dig. DCN (77) DMX (77) 16042066**

Third Gen.: Bulletin T-84-30 "ECM-PROM Incompatibility". ----------- D Fed. DMW (16) DMW (16) 16042063 D Cal. DMJ (25) DRD (26) 16042787 D Export DMK (35) DMK (35) 16042036 D Opt. Axle DMU (124) DMU (124) 16042060 E/K Fed. DMY (47) DMY (47) 16042069** E/K Cal. DMM (55) DMM (55) 16042042 E/K Export DMP (65) DMP (65) 16042048 E/K & E Conv. DLZ (154) DLZ (154) 16042010 Opt. Axle E Fed. Conv. DMA (46) DMA (46) 16042014 E Cal. Conv. DMC (56) DMC (56) 16042020 E/K Fed. Dig. DMX (77) DMX (77) 16042066**

* * See Serviceman Bulletin T-85-10 "EGR Valve PROM Incompatibility" before replacing PROM.

1984 D, E, AND K EQUIPPED WITH 4.1L DFI V-8 ENGINE SERVICE ECM PN 1226028 OR 1226930 (SEE BULLETIN 84-84) ------------------------------------------------------

Production Service Broadeast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number ----------- ------------ ----------- Third Gen.: Bulletin T-84-30 (continued) ---------- E/K Cal. Dig. DMN (85) DMN (85) 16042045 E/K Export Dig. DMR (95) DMR (95) 16042051 E/K & E Conv. DLW (184) DLW (184) 16042000 Opt. Axle Dig. E Fed. Conv. Dig. DMB (76) DMB (76) 16042017 E Cal. Conv. Dig. DMD (86) DMD (86) 16042024

Fourth Gen.: Bulletin T-84-55A "52-60 mph Surge or Chuggle". ----------- DM/DW Cal. DRD (26) DRD (26) 16042787 DM/DW Fed.* PROM's available DMW (101) 1227322 E/K Fed.* only for retrofit DMY (133) 1227323 E/K Cal.* CTP (57) 1226835 E/K Fed. Dig.* DMX (163) 1227324 E/K Cal. Dig.* CTT (87) 1226836 E Fed. Conv.* DMA (134) 1227325 E Fed. Conv. Dig.* DMB (164) 1227326

* These PROM's to be applied only to correct 52-60 mph surge or chuggle. Use Third Gen. for regular service replacement. Before applying the PROM, see Serviceman Bulletin T-84-55A for specific diagnoses that must be performed.

PROM I.D. is ECM data parameter .1.3

1984 J EQUEPPED WITH 2.0L EFI L-4 ENGINE SERVICE ECM P/N 1226458 ----------------------- Service Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number --------------- --------------- --------- ----------- First Gen.: ---------- Fed. Auto. BHW BHW 7348 16037347 Fed. Auto. BHX BHX 7353 16037352 Opt. Axle Cal. Auto. BHZ BHZ 7380 16037379 Fed. Manual BHU DFX 1533 16040496 Cal. Manual BHN DHA 2099 16042098

Second Gen.: Special Policy Adjustment Bulletin 84-P-1 reissue* ------------ Fed. Auto. FBU FBU 4136 1227256 Fed. Auto. FBW FBW 4139 1227257 Opt. Axle

Third Gen.: ----------- Fed. Auto. * * FBU FBU 4136 1227256 Fed. Auto. FBW FBW 4139 1227257 Opt. Axle** Fed. Manual DFX DFX 1533 16040496 Cal. Manual DHA DHA 2099 16042098

* Retrofit for cold startability only.

* * Retrofit for cold startability (see Special Policy Adjustment Bulletin 84-P-1 reissue).

PROM I.D.'s are on a sticker on top of the PROM.

1985 D, E, AND K EQUIPPED with 4.1L DFI V-8 ENGINE SERVICE ECM PN 1226930 ----------------------

Production Service Latest Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number ----------- ----------- ----------- First Gen.: ----------- D Fed. DJZ (19) HYA (102) 16056001 D Cal. DKA (28) DKA (28) 16043757 D Export DMK (35) DMK (35) 16042036 D Opt. Axle DKB (126) HYH (127) 16056103 E/K Fed. DKD (130) DKD (137) 1227382 E/K Cal. DKH (59) DKH (142) 1227389 E/K Export DMP (65) DMP (65) 16042048 E/K & E Conv. DKK (157) DKK (159) 1227387 Opt. Axle E Fed. Conv. DKM (131) DKM (138) 1227384 E Cal. Conv. DKM (131) DKM (138) 1227384 E/K Fed. Dig. DKF (160) DKF (167) 1227383 E/K Cal. Dig. DKJ (88) DKJ (171) 1227390 E/K Export Dig. DMR (95) DMR (95) 16042051 E/K & E Conv. DKL (187) DKL (189) 1227388 Opt. Axle Dig. E Fed. Conv. Dig. DKN (161) DKN (168) 1227385 E Cal. Conv. Dig. DKN (161) DKN (168) 1227385

Second Gen.: Bulletin 86-8 Federal, 86-9 California "52-60 mph Surge or ----------- Chuggle".

D Fed. HYA(102) HYA (102)* 16056001 HYA (103)*** 1227381 D Cal. DKA (28) DKA (28)* 16043757 DKA (110)* 1227629 DExport DMK (35) DKM (35) 16042036 D Opt. Axle HYH (127) HYH (127)* 16056103 HYH (128)** 1227386 E/K Fed. DKD (130) DKD (137) 1227382 E/K Cal. DKH (59) DKH (142) 1227389 E/K Export DMP (65) DMP (65) 16042048 E/K & E Conv. DKK (157) DKK (159) 1227387 Opt. Axle E Fed. Conv. DKM (131) DKM (138) 1227384 E Cal. Conv. DKM (131) DKM (138) 1227384 E/K Fed. Dig. DKF (160) DKF (167) 1227383 E/K Cal. Dig. DKJ (88) DKJ (171) 1227390 E/K Export Dig. DMR (95) DMR (95) 16042051 E/K & E Conv. DKL (187) DKK (189) 1227388 Opt. Axle Dig. E Fed. Conv. Dig. DKN (161) DKN (168) 1227385 E Cal. Conv. Dig. DKN (161) DKN (168) 1227385

* Regular service replacement PROM. ** Retrofit (revised) service PROM for condition described in bulletin.

1985 FWD C SERVICE ECM P/N 1226462 -----------------------

Production Service Latest Broadcast Code Broadeast Code Service PROM (PROM I.D.) (PROM I.D.) Number First Gen.: ----------- ----------- ------ ----------- C FWD Fed. DJK (211) HMC (215) 16052276 C Limousine DJK (211) HMC (215) 16052276 Com.Chassis C FWD Cal. DJL (222) HMD (226) C FWD Export BMB (230) BMB (230) 16037553

Second Gen.: ------------ C FWD Fed. DJM (213) HMC (215) 16052276 C Limousine DJM (213) HMC (215) 16052276 Com. Chassis C FWD Cal. DJN (223) HMD (226) 16052282

Third Gen.: ------------ C FWD Fed. DSM (214) HMC (215) 16052276 C Limousine DSM (214) HMC (215) 16052276 Com. Chassis C FWD Cal. DSN (225) HMD (226) 16052282

Fourth Gen.: Bulletin T-85-110 "False Code E13, Improved Shift Pleasability". ------------ C FWD Fed. HMC (215) HMC (215) 16052276 C Limousine HMC (215) HMC (215) 16052276 Com.Chassis C FWD Cal. HMD (226) HMD (226) 16052282

Fifth Gen.: Bulletin 87-30 "Engine May Stop Running with Power Steering Load ----------- During Park-to-Reverse Maneuvers.

C FWD Fed. HMC (215) HMC (215)* 16052276 HMC (216)** 1228112 C Limousine HMC (215) HMC (215)* 16052276 Com.Chassis HMC (216)** 1228112 C FWD Cal. HMD (226) HMD (226)* 16052282 HMD (227)**

* Regular service replacement PROM.

* * Retrofit (revised) service PROM for condition described in bulletin.

PROM I.D. is ECM data parameter .1.3

1985 J EQUIPPED WITH 2.0L EFI L-4 ENGINE SERVICE ECM PN 1226867 ----------------------

Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number -------------- -------------- --------- ------------ 2.0L First Gen.: ------------- Fed. Auto. DLJ HTL 4811 16054810 Cal. Auto. CRP HTM 4816 16054815 Fed. Manual CRJ HHD 6740 1228361 Cal. Manual CRL HHH 6760 1228363

Second Gen.: ------------ Fed. Auto. HDU HTL 4811 16054810 Cal. Auto. HDW HTM 4816 16054815 Fed. Manual HBD HHD 6740 1228361 Cal. Manual HHH HHH 6760 1228363

Third Gen.: Bulletin T-85-104 "False Setting of Check Engine Light Trouble ----------- Code 44".

Fed. Auto. HTL HTL 4811 16054810 Cal. Auto. HTM HTM 4816 16054815

Fourth Gen.: Idle stall or idle surge. ------------ Fed. Manual HHD HHD 6740 1228361 Cal. Manual HHH HHH 6760 1228363

Fifth Gen.: Bulletin T-88-113 "Light Throttle Detonation". ------------ Fed. Auto. ANBW ANBW 2971 16122999 Cal. Auto. ANBX ANBX 2981 16123000

1985 J EQUIPPED WITH 2.8L PFI V-6 ENGINE SERVICE ECM P/N 1226870 2.8L ----------------------- First Gen.: ------------ Fed. Auto. CXM FPU 1360 1228114 Cal. Auto. CXP FPX 1363 1228116 Fed. Manual CXS FPZ 2044 16052043 Cal. Manual CXU FRB 2093 16052092

Second Gen.: Bulletin 87-5 "Surge or Chuggle at 32-40 mph in 3rd Gear". ------------ Fed. Auto. FPU FPU 1360 1228114 Cal. Auto. FPX FPX 1363 1228116

PROM I.D.'s are on a sticker on top of the PROM.

1986 FWD C EQUIPPED WITH 4.1L DFI V-8 ENGINE SERVICE ECM IN 1227056 ------------------------

Production Service Latest Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number First Gen.: ----------- ----------- ----------- ---------- C FWD Fed. HMU (253) AFS (255) 16059149 C FWD Cal. FCS (261) AFM (262) 16059167 C FWD Export FCW (341) FCW (341) 16053017 C FWD Limousine FCX (254) AFN (256) 16059163 C FWD Fed. Opt. FCU (257) FCU 257) 16053013 Axle (GX3) C FWD Cal. Opt. HMW (263) HMW (263) 16053044 Axle (GX3)

Second Gen.: Bulletin 86-66 "Detonation at High MAP, High RPM" ----------- C FWD Fed. AFS (255) AFS (255) 16059149 C FWD Cal. AFM (262) AFM (262) 16059167 C FWD Limousine AFN (256) AFN (256) 16059163

Third Gen.: Bulletin 87-75 "Engine May Stop Running During Parking Maneuvers ---------- or During Coast Down at Low Speeds During Ambient Temperature Above 85 DEG F".

C FWD Fed. AFS (255) AFS (255)* 16059149 AFS (258)** 1228129 C FWD Cal. AFM (262) AFM (262)* 16059167 AFM (264)** 1228130 C FWD Limousine AFN (256) AFS (258) 1228129

* Regular service replacement PROM.

* * Retrofit (revised) service PROM for condition described in bulletin.

PROM I.D. is parameter .1.3

1986 E/K EQUIPPED WITH 4.1L DFI V-8 ENGINE SERVICE ECM P/N 1227056 ------------------------

Production Service Latest Broadeast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number ----------- ----------- ----------- First Gen.: ----------- E/KFed. FDF (303) AFR (306) 1228588 E/KCal. FDC (321) AFP (324) 1228587 PE/K Export FDH (340) FDH (340) 16053062

Second Gen.: Bulletin 87-76 "Engine May Stop Running During Drive Coast Down ------------ at Low Speeds with Hot Ambient Temperatures".

E/K Fed. AFR (304) AFR (306) 1228588 E/KCal. AFP (322) AFP (324) 1228587

Third Gen.: Bulletin 87-76A, 88-23 "Code E48 and Engine May Stop Running with ----------- Power Steering Load During Park-to-Reverse Maneuvers".

E/KFed. AFR (306) AFR (306) 1228588 E/KCal. AFP (324) AFP (324) 1228587

PROM I.D. is ECM data parameter .1.3

1986 D EQUUIPPED WITH 5.0L CCC V-8 ENGINE SERVICE ECM P/N 1227301 -----------------------

Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number -------------- -------------- ---------- ------------ First Gen.: ---------- D Fed. FNU AAND 2798 16062797 D Cal. FNW AANF 2802 16062801 D Export ABN AAHD 1147 16061146

Second Gen.: ------------ D Fed. AAND AAND 2798 16062797 D Cal. AANF AANF 2802 16062801 D Export AAHD AAHD 1147 16061146

Third Gen.: Bulletin 87-126 "False Code 44 on Long Coast Down". ----------- D Fed. AAND AAND 2798* 16062797 AAND 1050** 1228486 D Cal. AANF AANF 2802* 16062801 AANF 1052** 1228487 D Export AAHD AAHD 1147 16061146

* Regular service replacement PROM.

* * Retrofit (revised) service PROM for condition described in bulletin.

PROM I.D.'s are on a sticker on top of the PROM.

1986 J EQUIPPED WITH 2.0L EFI L-4 ENGINE SERVICE ECM P/N 1227165 ------------------------

Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number -------------- --------------- ---------- ----------- First Gen.: ---------- Fed. Auto. HTC CTZ 0566 16060565 Cal. Auto. HTD HTD 5293 16055292 Fed. Manual CRY CRY 6807 1228368 Cal. Manual CSA CSA 6810 1228369

Second Gen.: ------------- Fed. Auto. CTZ CTZ 16060565

Third Gen.: Idle stall or idle surge. ----------- Fed. Manual CRY CRY 6807 1228368 Cal. Manual CSA CSA 6810 1228369

Fourth Gen.: Bulletin T-88-113 "Light Throttle Detonation". ------------ Fed. Auto. ANBW ANBW 2971 16122999 Cal. Auto. ANBX ANBX 2981 16123000

1986 J EQUIPPED WITH 2.8L V-6 ENGINE SERVICE ECM PN 1227302 ----------------------- First Gen.: ----------- Fed. Auto. HKS ANPS 6446 16126446 Cal. Auto. HKX ANPU 6448 16126448 Fed. Manual HKT HKT 5335 16055333 Four Speed Cal. Manual HKY HKY 5343 16055342 Four Speed

Second Gen.: Bulletin 87-5 "Surge or Chuggle at 32-40 mph". ----------- Fed. Auto. HKS ANPS 6446 16126446 Cal. Auto. HKX ANPU 6448 16126448

Third Gen.: Bulletin 88-152 "Engine Stall, Hesitation or Idle Surge Following --------- Cold Start Only".

Fed. Auto. HKS ANPS 6446 16126446 Cal. Auto. HKX ANPU 6448 16126448

PROM I.D.'s are on a sticker on top of the PROM.

1987 C, E, AND K EQUIPPED WITH 4.1L DFI V-8 ENGINE SERVICE ECM P/N 1227056 -----------------------

Production Service Latest Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Part Number First Gen.: ----------- ----------- ----------- ----------- C Fed. ABPZ (272) AFTS (274) 16075422 C Fed. Opt. CKA (271) CKA (271) 16062406 Axle (GX3) C Cal. CJM (267) AFTT (268) 16075435 C Cal. Opt. CKB (266) CKB (266) 16062413 Axle (GX3) C Limousine CKC (273) CKC (273) 16062417 E/K Fed. ABPX (311) ABPX (311) 16066646 E/K Cal. ABPY (327) ABPY (327) 16066654 E/K Export FDH (340) FDH (340) 16053062

Second Gen.: Bulletin 87-56 "Hesitation on Acceleration". ----------- C FED. AFTS (274) AFTS (274) 16075422 C CAL. AFTT (268) AFTT (268) 16075435

1987 D EQUIPPED WITH 5.0L CCC V-8 ENGINE SERVICE ECM P/N 1227301 -----------------------

Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number First Gen.: --------------- -------------- ---------- ----------- ----------- D Fed. AAND AAND 2798 16062797 D Cal. AANF AANF 2802 16062801 D Export AAHD AAHD 1147 16061146

Second Gen.: Bulletin 87-126 "False Code 44 on Long Coast Down". ------------ D Fed. AAND AAND 2798* 16062797 AAND 1050** 1228486 D Cal. AANF AANF 2802* 16062801 AANF 1052** 1228487*

* Regular service replacement PROM.

** Retrofit (revised) service PROM for condition described in bulletin.

1987 V EQUIPPED WITH 4.1L PFI V-8 ENGINE SERVICE ECM P/N 1227750 ------------------------ PROM I.D./ Service PROM Trans. I.D. Broadcast Code Part Number ----------- -------------- ----------- First Gen.: 7AAZ 543/AHWY 16077504 ---------- Second Gen.: 7APZ 544/AKAA 16076500 ------------ or 545/ADBC

#### NOTE: PROM I.D. must be matched to transmission I.D.; they are not interchangeable.

1987 J EQUIPPED WITH 2.8L PFI V-6 ENGINE SERVICE ECM P/N 1227730 ----------------------- Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number -------------- -------------- ---------- ----------- First Gen.: ----------- J Fed. Auto. ADDB ADRY 8533 1228533 J Fed. Manual ADDH AMZJ 0971 16120949 J Cal. Auto. ADDC ADRZ 8534 1228534 J Cal. Manual ADDJ AMZK 0981 16120953

Second Gen.: Bulletin 87-70 "False Code 43". ----------- J Fed. Auto. ADRY ADRY 8533 1228533 J Fed. Manual ADSC AMZJ 0971 16120949 J Cal. Auto. ADRZ ADRZ 8534 1228534 J Cal. Manual ADSD AMZK 0981 16120953

Third Gen.: Bulletin 88-86 "Stall After Start, Stall During Deceleration, or --------- Hesitation Cold".

J Fed. Auto. ADRY ADRY 8533 1228533 J Fed. Manual ADSC AMZJ 0971 16120949 J Cal. Auto. ADRZ ADRZ 8534 1228534 J Cal. Manual ADSD AMZK 0981 16120953

1988 C, E, AND K EQUIPPED WITH 4.5L DFI V-8 ENGINE SERVICE ECM P/N 1228322 -----------------------

Production Service Latest Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) (PROM I.D.) ------------ ----------- ----------- First Gen.: ----------- C Fed. AKYA (701) AMNS (850) 16089317 C Cal. ADBK (702) AMNT (851) 16089322 C Limousine ADBP (703) ADBP (703) 16077616 Com. Chassis E/K Fed. AKYB (861) AMNP (1000) 16089308 E/K Cal. ADBF (862) AMNR (1001) 16089313 K STS Fed. AMYW (1002) AMYW (1002) 16120924 K STS Cal. AMYX (1003) AMYX (1003) 16120931

Second Gen.: Bulletin 88-106 "Cruise Control Inoperative Code E67 and/or ----------- Cruise Control Resume Does Not Return to Set Speed".

C Fed. AMNS (8500 AMNS (850) 16089317 C Cal. AMNT (851) AMNT (851) 16089322 E/K Fed. AMNP (1000) AMNP (1000) 16089308 E/K Cal. AMNR (1001) AMNR (1001) 16089313

1988 V EQUIPPED WITH 4.1L PFI V-8 ENGINE SERVICE CEM P/N 1227750 ----------------------- First Gen.: ------------ V ADBC (545) ADBC (545) 16076500

1988 D EQUIPPED WITH 5.0L CCC V-8 ENGINE SERVICE ECM P/N 1228330 ----------------------- Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number First Gen.: --------------- -------------- --------- ----------- ----------- D Fed. ADAY ALUP 2182 16122177 D Cal. ADAZ APSW 2057 16132056 D Export ADBA ADBA 7533 16077532

Second Gen.: Bulletin 89-39 "Insufficient A/C Cooling When Driving".

D Fed. ALUP ALUP 2182 16122177 D Cal. APSW APSW 2057 16132056

1988 J EQUIPPED WITH 2.8L PFI V-6 ENGINE SERVICE ECM PN 1227730 ----------------------- First Gen.: ----------- J Fed. Auto. AKDN ANWD 8991 16128936 J Fed. Manual AKDM ANWL 8981 16128934 J Cal. Auto. AKDK ANWB 8971 16128933 J Cal. Manual AKDP ANWF 9001 16128937

Second Gen.: Bulletin 89-17 "Engine Stall, Only After Cold Start, or Idle ----------- Surge May Set Code 35".

J Fed. Auto. ANWD ANWD 8991 16128936 J Fed. Manual ANWC ANWC 8981 16128934 J Cal. Auto. ANWB ANWB 8971 16128933 J Cal. Manual ANWF ANWF 9001 16128937

Third Gen.: Bulletin 89-17A "Tip In Hesitation On Acceleration, Engine Stall ----------- On Cold Start or Engine Stall On Deceleration".

J Fed. Auto. ARDC ARDC 4761 16134468 J Fed. Manual ARDB ARDB 4751 16134466 J Cal. Auto. ARDA ARDA 4741 16134465 J Cal. Manual ARDD ARDD 4771 16134482

1989 C, E, AND K EQUIPPED WITH 4.5L DFI V-8 ENGINE SERVICE ECM P/M 1229322 -----------------------

Production Service Latest Broadcast Code Broadcast Code Service PROM (PROM I.D.) (PROM I.D.) Number First Gen.: ------------ ------------- ------ ------------ C Fed. ALCK (344) ALCK (344) 16086013 C Cal. ALCL (346) ALCL (346) 16084446 C Export ALCN (349) ALCN (349) 16084466 C Com. Chassis ALCM (348) ALCM (348) 16084456 E/K Fed. ALCP (1004) ALCP (1004) 16084476 E/K Cal. ALCR (1006) ALCR (1006) 16084486 E/K Export ALCS (1008) ALCS (1008) 16084496 E/K Fed. Opt. AMZA (1005) AMZA (1005) 16120846 Axle (GX3) E/KCal AMZB (1007) AMZB (1007) 16120856 Axle (GX3)

1989 V EQUIPPED WITH 4.5L PFI V-8 ENGINE SERVICE ECM P/N 1227750 ----------------------- First Gen.: ----------- V ANZR (2002) ANZR (2002) 16129601

1989 D EQUIPPED WITH 5.0L CCC V-8 ENGINE SERVICE ECM P/N 1228330 ----------------------- Service Latest Production Service PROM Service PROM Broadcast Code Broadcast Code Part I.D. Part Number First Gen.: -------------- -------------- ---------- ----------- ------------ D Fed. ALUP ALUP 2182 16122177

D Cal. APSW APSW 2057 16132056

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.