Air Induction System - Propane Leak Test Procedure
89ford36^ AIR INDUCTION SYSTEM - 3.8L "SUPERCHARGED" - PROCEDURE FOR LOCATING INDUCTION SYSTEM LEAKS BY USING PROPANE
^ IDLE - ROUGH - 3.8L "SUPERCHARGED" - INDUCTION SYSTEM LEAKS - LOCATING PROCEDURE USING PROPANE
^ STALLS - 3.8L "SUPERCHARGED II - INDUCTION SYSTEM LEAKS - LOCATING PROCEDURE USING PROPANE
Article No. 89-25-7
FORD: 1989 THUNDERBIRD
LINCOLN-MERCURY: 1989 COUGAR
ISSUE: Air leaks in the air induction system can cause the engine to run lean. This may cause a rough idle condition or a stalling condition at idle. Proper assembly of the intercooler system is very important to prevent air leaks.
ACTION: Use the following propane testing and service procedure check for air leaks. Also use the following service procedure to seal any leaking connections.
The intercooler system should be checked for leaks whenever the following occur.
^ The intercooler system is reassembled after any service procedure.
^ There is a drive concern with symptoms typical of an air leak. (A leak may also be indicated by Self-Test Codes 41 and 91 - system always lean.)
PROPANE TESTING PROCEDURE
1. Inspect all flange joints for signs of leaks.
2. Bring the engine to normal operating temperature.
3. Connect an EEC-IV Monitor Tester to read the rich/lean state of the EGO sensors (Code 41 or 91 on EEC-IV Star Test).
WARNING: MAKE SURE THE CAR IS IN A WELL VENTILATED AREA AWAY FROM ANY SOURCE OF SPARK OR FLAME WHEN USING PROPANE.
4. With the engine idling in Neutral or Park and the parking brake set, spray small amounts of propane around the following areas:
^ Flange joint at the rear of the supercharger
^ By-pass hose connections at the rear of the supercharger
^ Flange joint at the supercharger outlet adapter
^ Tube joint at supercharger outlet to the upper tube
^ Tube joint at upper intercooler inlet
^ Tube joint at lower intercooler outlet
^ Tube joint at intake manifold adapter inlet
^ Intake manifold adapter to intake manifold flange
5. The EGO monitor box will indicate "RICH" Red Light for one or two seconds, then return to normal switching when propane is sprayed near an induction system air leak. The EGO monitor box will indicate "LEAN" Green Light after one or two seconds when the propane is removed from the leak.
6. If a leak is found, retighten the nuts at all tube flange locations and at the supercharger outlet adapter "collar". Refer to the following "Mini-Sealing Procedure".
NOTE: SPANNER NUT WRENCH, T89P-6634-A IS REQUIRED TO PERFORM THE MINI-SEALING PROCEDURE.
7. If a leak is still present after performing the "Mini-Sealing Procedure", the entire induction system must be disassembled and the sealing surfaces cleaned. Refer to the 1990 Thunderbird/Cougar Shop Manual, Section 24-43 for service details.
8. If no leak is found, refer to the 1989 Engine/Emissions Diagnosos Manual, Volume H, Section 2, Diagnostic Routines.
MINI-SEALING PROCEDURES
LEAK AT INTERCOOLER/TUBE CONNECTIONS
For leaks at the joint between the intercooler and the inlet or outlet tube, proceed as follows:
1. Slightly loosen the nut that attaches the inlet tube to the alternator-power steering bracket.
2. Re-torque the nuts at the intercooler flanges to 15-22 lb.ft. (20-30 N-m).
3. Re-torque the nuts at the alternator-power steering pump bracket to 30-40 lb.ft. (40-55 N-m).
4. Test all joints with propane.
LEAK AT SUPERCHARGER OUTLET ADAPTOR/TUBE CONNECTION
For leaks at the supercharger outlet adapter "collar" and the inlet tube joint, proceed as follows:
1. Slightly loosen the nut that attaches the inlet tube to the alternator-power steering pump bracket.
2. Re-torque the "collar" to 148 lb.ft. (200 N-m).
3. Wait a minimum of ten (10) minutes and re-torque the "collar" to 148 lb.ft. (200 N-m).
NOTE: WHEN COMPRESSED, THE SEALANT TAPE FLOWS AND FORMS TO THE SEALING SURFACE. IF THE "COLLAR" IS NOT RE-TORQUED, THE TORQUE OF THE "COLLAR" WILL DROP CAUSING A LEAK AT THIS JOINT.
4. Re-torque the nut at the alternator-power steering pump bracket to 30-40 lb.ft. (40-55 N-m).
5. Test all joints with propane.
LEAK AT INTAKE ELBOW ADAPTOR/OUTLET TUBE CONNECTION
For leaks at the intake elbow adapter to outlet tube joint, proceed as follows:
1. Slightly loosen the nut that attaches the outlet tube to the alternator-power steering pump bracket.
2. Loosen the bolt that attaches the outlet tube to the cylinder block support bracket (bottom).
3. Re-torque the nuts at the intake elbow adapter to 15-22 lb.ft. (20-30 N-m).
4. Re-torque the nut at the alternator-power steering pump bracket to 30-40 lb.ft. (40-55 N-m).
5. Re-torque the bolt that attaches the outlet tube to the cylinder block support bracket to 30-40 lb.ft. (40-55 N-m).
6. Test all joints with propane.
PART NUMBER PART NAME CLASS
E9PZ-6F091-A Propane Leak Testing Kit CG
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Eligible Under Basic Warranty Coverage, Powertrain Warranty Coverage
OPERATION DESCRIPTION TIME
892507A Locate Induction System 1.2 Hrs.
Leak
892507B Seal Air Leak 1.0 Hr.
DEALER CODING
BASIC PART NO. CONDITION CODE
6F072 48
OASIS CODES: 4700, 4800, 620100, 620800