INFO. ON FLUID INDUCTION SYS. REPAIR/SERVICE PARTS. Cadillac Eldorado 1994

SUBJECT: INFORMATION ON FLUID INDUCTION SYSTEM (INTAKE MANIFOLD) REPAIR PROCEDURES AND SERVICE PARTS

MODELS: 1993 CADILLAC ALLANTE 1993-94 CADILLAC ELDORADO AND SEVILLE WITH 4.6L NORTHSTAR ENGINE (VINS Y AND 9 - RPOS LD8 AND L37)

OUTLINED BELOW ARE APPROPRIATE SERVICE PROCEDURES AND AVAILABLE SERVICE PART KITS FOR SERVICING THE FLUID INDUCTION SYSTEM (INTAKE MANIFOLD). DURING THE 1993 MODEL YEAR, GROMMET STYLE TOP COVER FASTENERS WERE INCORPORATED INTO THE FLUID INDUCTION SYSTEM. WHEN REPLACING A TOP COVER OR LOWER HOUSING, THE FLUID INDUCTION SYSTEM MUST BE UPDATED WITH THE NEW GROMMET STYLE TOP COVER, GROMMET FASTENERS, FUEL INJECTOR WIRING HARNESS COVER AND GASKET. USE THE FOLLOWING GUIDELINES TO DETERMINE WHICH STYLE TOP COVER IS ON THE FLUID INDUCTION SYSTEM (SEE FIGURE 1).

PROCEDURE:

TOP COVER DURING THE 1993 MODEL YEAR, A "GROMMET" STYLE FASTENING SYSTEM WAS INCORPORATED INTO THE TOP COVER. THESE FASTENING DESIGN CHANGES INCLUDE 12 TORX HEAD SCREWS (2 - SILVER IN COLOR), 12 OVAL SHAPED RUBBER SPACERS WITH STEEL WASHERS AND A RAISED STEP ON THE TOP COVER TO ACCOMMODATE THE NEW SCREWS AND SPACERS (SEE FIGURE 1). THESE NEW TOP COVER ENHANCEMENTS INCLUDE A NEW DESIGN WIRING HARNESS COVER, GASKET AND IGNITION WIRE HARNESS CHANNEL. ALONG WITH THESE NEW TOP COVER ENHANCEMENTS, A NEW DESIGN WIRING HARNESS COVER AND GASKET ARE ALSO USED.

WHEN TOP COVER REPLACEMENT IS NECESSARY:

1. INSPECT THE TOP COVER FOR RUBBER GROMMETS BENEATH THE COVER SCREWS AND RAISED STEP ON THE COVER. IF THESE FEATURES ARE PRESENT, INSTALL A NEW TOP COVER, PART NUMBER 17090937. REFER TO INSTALLATION PROCEDURES DESCRIBED IN THIS BULLETIN BELOW.

2. IF THE TOP COVER IS A NON-GROMMET DESIGN, REPLACE THE TOP COVER WITH THE "GROMMET STYLE" COVER KIT, PART NUMBER 17113193, WHICH CONTAINS: GROMMET BOLT STYLE COVER GROMMET STYLE BOLTS (12 TORX HEAD SCREWS WITH SPACERS) WIRING HARNESS COVER GASKET SPARK PLUG WIRE CHANNEL

3. REFER TO THE INSTRUCTIONS IN THIS BULLETIN FOR CHANGING THE FLUID INDUCTION SYSTEM COVER AND GASKET. NOTE: IF THE NEW STYLE GASKET IS **NOT** USED WHENEVER TOP COVER REPLACEMENT IS NECESSARY, THE NEW TOP COVER AND GROMMET STYLE FASTENERS WILL BE INEFFECTIVE IN THEIR DESIGNED FUNCTION.

LOWER HOUSING WHEN LOWER HOUSING REPLACEMENT IS NECESSARY:

1. INSPECT THE TOP COVER AND DETERMINE IF THE GROMMET STYLE TOP COVER IS USED. IF SO, REPLACE THE LOWER HOUSING USING PART NUMBER 17112975.

2. IF THE TOP COVER IS **NOT** A GROMMET STYLE DESIGN, INSTALL THE "GROMMET STYLE" COVER KIT, REFERRING TO THE SAME INSTALLATION PROCEDURES USED FOR THE TOP COVER AND GASKET.

**ADDITIONAL COMPONENTS CONTAINED IN THE FLUID INDUCTION SYSTEM ASSEMBLY REQUIRING REPLACEMENT CAN BE REPLACED USING THE SERVICE PROCEDURES OUTLINED BELOW.**

CHANGING THE COVER AND GASKET ASSEMBLY DISASSEMBLING THE PREVIOUS GASKET ASSEMBLY ------------------------------------------ CAUTION: TO REDUCE THE RISK OF FIRE AND PERSONAL INJURY, IT IS NECESSARY TO RELIEVE THE FUEL SYSTEM PRESSURE BEFORE SERVICING FUEL SYSTEM COMPONENTS.

AFTER RELIEVING SYSTEM PRESSURE, A SMALL AMOUNT OF FUEL MAY BE RELEASED WHEN SERVICING FUEL LINES OR CONNECTIONS. TO REDUCE THE CHANCE OF PERSONAL INJURY, COVER FUEL LINE FITTINGS WITH A SHOP TOWEL BEFORE DISCONNECTING TO CATCH ANY FUEL THAT MAY LEAK OUT. PLACE THE TOWEL IN AN APPROVED CONTAINER WHEN DISCONNECT IS COMPLETE.

1. RELIEVE FUEL SYSTEM PRESSURE (REFER TO SERVICE MANUAL).

2. DISCONNECT THE SPARK PLUG HARNESS CHANNEL ATTACHED TO THE MANIFOLD COVER. IT IS LOCATED ON THE RIGHT-HAND SIDE AND RUNS ACROSS THE THROTTLE BODY AND OVER THE WATER PUMP PULLEY BELT; MOVE HARNESS CHANNEL ASIDE.

3. REMOVE THE CRANKCASE VENTILATION HOSE FROM THE TOP OF THE AIR INLET DUCT.

4. REMOVE THE AIR INLET DUCT FROM THE THROTTLE BODY AND FROM THE AIR CLEANER ASSEMBLY.

5. DISCONNECT THE ELECTRICAL CONNECTOR(S) LEADING TO THE MANIFOLD ASSEMBLY.

6. REMOVE THE TWELVE (12) SCREWS FROM THE TOP COVER. DISCARD THE SCREWS.

7. REMOVE THE TOP COVER. DISCARD THE TOP COVER.

8. GENTLY PULL UP ON THE GASKET ASSEMBLY FROM THE LOWER MANIFOLD ASSEMBLY. THE FUEL INLET AND OUTLET FITTINGS ARE LOCATED UNDER THE GASKET NEAR THE THROTTLE BODY AND WILL DISCONNECT BY PULLING THE GASKET UPWARD.

THERE MAY BE A RELEASE OF RESIDUAL FUEL IN THE FUEL RAIL ASSEMBLY WHEN THE INLET AND OUTLET FITTINGS ARE DISCONNECTED. USE A SHOP TOWEL TO SOAK UP EXCESS FUEL IN THE LOWER MANIFOLD ASSEMBLY.

9. ONCE THE GASKET IS FREE OF THE LOWER MANIFOLD ASSEMBLY, FEED THE ELECTRICAL WIRING HARNESS UP THROUGH THE MANIFOLD ASSEMBLY.

10. PLACE THE GASKET ASSEMBLY ON A CLEAN, FLAT WORK SURFACE.

11. REMOVE THE WIRING HARNESS COVER WHICH IS SNAPPED IN PLACE ON THE TOP SIDE OF THE GASKET COVERING THE INJECTOR WIRING. DISCARD THE WIRING HARNESS COVER.

12. REMOVE THE ELECTRICAL CONNECTIONS FROM THE MAP SENSOR, FUEL INJECTORS (8), AND REMOVE THE IAT SENSOR FROM THE GASKET. (THE IAT SENSOR DOES NOT HAVE TO BE ELECTRICALLY DISCONNECTED.) CAREFULLY PULL THE INJECTOR WIRE LEADS (8) THROUGH THE SLOTS IN THE GASKET BEING CAREFUL NOT TO DAMAGE THE INSULATION ON ANY OF THE WIRES. NOTE: DO NOT REMOVE THE FUEL INJECTORS FROM THE INJECTOR PODS ON THE FUEL RAIL.

13. FROM THE BOTTOM SIDE OF THE GASKET, TURN THE ELECTRICAL GROMMET CLOCKWISE AND PUSH THE WIRES THROUGH THE GASKET. SET THE WIRING HARNESS ASIDE--IT WILL BE REINSTALLED ON THE NEW GASKET.

14. REMOVE THE MAP SENSOR FROM THE GASKET BY LIFTING UP ON THE ELECTRICAL CONNECTOR SIDE OF THE SENSOR TO REMOVE IT FROM THE GASKET HOLDER. THEN SLIDE THE SENSOR IN THE DIRECTION OF THE ELECTRICAL CONNECTOR. SET THE MAP SENSOR ASIDE TO BE REINSTALLED IN THE NEW GASKET.

15. ON THE TOP SIDE OF THE GASKET, BEGINNING AT THE FUEL INLET SIDE OPPOSITE THE FUEL REGULATOR, CAREFULLY REMOVE THE FUEL INLET, FUEL INJECTOR PODS (8), AND THE FUEL PRESSURE REGULATOR FROM THE GASKET BEING CAREFUL NOT TO DAMAGE THE PLASTIC TABS.

16. DISCARD THE OLD GASKET.

ASSEMBLING THE NEW GASKET ASSEMBLY

1. INSTALL THE FUEL RAIL ASSEMBLY ONTO THE NEW GASKET. (THE NEW GASKET CAN BE IDENTIFIED BY THE METAL INSERTS FOR THE TOP COVER HOLD DOWN BOLTS.) BEGIN BY INSTALLING THE FUEL PRESSURE REGULATOR INTO THE FUEL PRESSURE REGULATOR HOLE AND WORK AROUND THE GASKET BY INSTALLING FUEL INJECTOR PODS (8). LASTLY, INSTALL THE FUEL INLET FITTING.

2. FEED THE WIRING HARNESS THROUGH THE GASKET AND LOCK THE PLASTIC HARNESS INTO THE GASKET; THERE WILL BE A NOTICEABLE CLICK WHEN LOCKED IN PLACE. ALSO, THE PLASTIC GUIDES FOR THE WIRE PATHWAY WILL LINE UP WITH THE PATHWAY ON THE GASKET.

3. FEED THE INJECTOR WIRES INTO THE PATHWAY AND CAREFULLY PULL THE FUEL INJECTOR CONNECTORS (8) THROUGH THE SLOTS SO AS NOT TO DAMAGE THE WIRE INSULATION.

4. CONNECT THE ELECTRICAL CONNECTORS (8) TO THE FUEL INJECTORS.

5. INSTALL THE MAP SENSOR INTO THE GASKET AND CONNECT THE WIRE CONNECTOR.

6. INSTALL THE IAT SENSOR INTO THE GASKET.

7. INSTALL THE NEW WIRING HARNESS COVER TO THE GASKET.

8. INSPECT TO SEE THE O-RINGS ON THE FUEL INLET AND PRESSURE REGULATOR ARE IN GOOD SHAPE AND THE O-RING RETAINER IN THE FUEL PRESSURE REGULATOR IS IN PLACE. IF NECESSARY, REPLACE THE O-RINGS (PART NUMBER 17107478 FOR THE FUEL REGULATOR AND 17081434 FOR THE FUEL INLET LINE) BY LUBRICATING THEM WITH A SMALL AMOUNT OF CLEAN OIL.

9. INSPECT THE LOWER INJECTOR SEALS AND REPLACE ANY THAT ARE DAMAGED OR MISSING (PART NUMBER 17113141).

10. APPLY A SMALL AMOUNT OF CLEAN OIL ON THE FUEL INLET AND FUEL RETURN TUBES IN THE MANIFOLD ASSEMBLY TO AVOID DAMAGE TO THE O-RINGS AND TO ASSIST IN REASSEMBLY.

11. REINSTALL THE GASKET ASSEMBLY INTO THE LOWER MANIFOLD ASSEMBLY BY FEEDING THE ELECTRICAL CONNECTOR(S) THROUGH THE LOWER MANIFOLD ASSEMBLY FIRST.

12. USING HAND PRESSURE ONLY, SEAT THE GASKET INTO THE LOWER MANIFOLD ASSEMBLY BY CAREFULLY WORKING THE GASKET DOWN UNTIL THE GASKET SEATS ON THE MANIFOLD.

13. RECONNECT THE ELECTRICAL CONNECTOR(S) LEADING TO THE MANIFOLD ASSEMBLY.

14. INSTALL THE NEW TOP COVER (PART NUMBER 17113144) USING THE NEW BOLTS MAKING SURE THE RUBBER GROMMETS ON THE SCREWS ARE PROPERLY ALIGNED WITH THE GUIDES ON THE COVER. THE SILVER SCREWS (2) ARE TO BE INSTALLED CLOSEST TO THE THROTTLE BODY AND THE BLACK SCREWS ARE TO BE INSTALLED IN THE REMAINING HOLES. NOTE: TIGHTEN THE COVER SCREWS USING A TORQUE WRENCH TO 8-11 N.M (71 LBS. IN.) **DO NOT OVERTIGHTEN.**

15. REINSTALL THE AIR INLET DUCT TO THE THROTTLE BODY AND THE AIR CLEANER ASSEMBLY.

16. REINSTALL THE CRANKCASE VENTILATION HOSE INTO THE AIR INLET DUCT.

17. RECONNECT THE SPARK PLUG WIRE CHANNEL TO THE MANIFOLD COVER AND REINSTALL THE COVERS OVER THE CHANNEL.

SERVICE PARTS INFORMATION: WHEN ORDERING PARTS FOR THE FLUID INDUCTION SYSTEM ASSEMBLY, REFER TO THE FOLLOWING PART NUMBERS:

DESCRIPTION PART NUMBER ----------- ----------- LOWER INTAKE MANIFOLD KIT 17112975 INTAKE MANIFOLD COVER GASKET 17090990 WIRING HARNESS ASSEMBLY W/GROMMET 12121172 COVER, WIRING HARNESS 17091325 SENSOR, MAP-2 WIRE CONNECTOR 17086148 SENSOR, MAP-3 WIRE CONNECTOR 16151999 MPFI MULTEC FUEL INJECTOR KIT 17113140 FUEL RAIL ASSEMBLY AND INJECTOR O-RINGS 17113142 FUEL PRESSURE CONNECTOR REPAIR KIT 17112556 GASKET, THROTTLE BODY TO MANIFOLD 17101798 MPFI THROTTLE BODY ASSEMBLY KIT 17112864 THROTTLE POSITION SENSOR 17106682 IDLE SPEED CONTROL ACTUATOR 17112866 THROTTLE BODY ATTACHMENT KIT 17112869 UPPER INTAKE MANIFOLD COVER 17090937 EMBLEM, COVER 17101635 COVER BOLT KIT 17113144 MPFI INJECTOR SEAL KIT 17113141 FUEL PIPE (FEED AND RETURN) KIT 17113143 THROTTLE BODY KIT 17094040 PRESSURE REGULATOR KIT 17107478

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

LABOR OPERATION: J0200 USE PUBLISHED LABOR TIME.

FIGURES: 1

Object Number: 87021 Size: FS

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