ENGINE COMPRESSION
Warm engine to normal operating temperature. Check compression at cranking speed with throttle wide open and all spark plugs removed. Ensure crankcase is at correct level and oil is correct viscosity. With compression gauge installed, use remote starter to crank engine.
Crank engine 5 revolutions (minimum) and record highest reading. Repeat procedure for all cylinders using approximately same number of revolutions. Lowest compression reading should not be less than 75 percent of highest compression reading. Cylinder compression readings should not be less than 100 psi (7 kg/cm 2 ).
| Application | Compression Ratio |
|---|
| 2.5L | 9.2:1 |
| 3.0L Except SHO | 9.3:1 |
| 3.0L SHO & 3.2L SHO | 9.8:1 |
| 3.8L Except SC | 9.0:1 |
| 3.8L SC | 8.2:1 |
COMPRESSION RATIO SPECIFICATIONS
VALVE CLEARANCE
Note. On 3.0L SHO and 3.2L SHO models, valve clearance is adjustable. On all other models, hydraulic valve lifters are used and valve adjustment is not required. If incorrect valve clearance is suspected, lifter must be collapsed before clearance can be checked.
| Application | In. (mm) |
|---|
| 3.0L Except SHO | .085-.185 (2.16-4.70) |
| 3.0L SHO & 3.2L SHO |
| Intake | (1) .006-.010 (.15-.25) |
| Exhaust | (1) .010-.014 (.25-.35) |
| 3.8L | .089-.189 (2.3-4.8) |
| (1) DO NOT collapse valve lifter for clearance check. |
| (1) | DO NOT collapse valve lifter for clearance check. |
COLLAPSED VALVE LIFTER CLEARANCE
IGNITION COIL
| Application | Primary (Ohms) | Secondary (Ohms) |
|---|
| 2.5L | 0.6-0.9 | 1150-18,500 |
| Except 2.5L |
| Distributorless Systems | (1) | (1) |
| All Other Systems | .8-1.6 | 8700-11,500 |
| (1) Resistance value is not available. For testing, see appropriate SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section. Refer to menu following this table. |
| (1) | Resistance value is not available. For testing, see appropriate SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section. Refer to menu following this table. |
- «SYSTEM/COMPONENT TESTS - EEC (2.5L)»(ref-22918) (Probe 2.5L)
- «SYSTEM/COMPONENT TESTS - EEC-IV (3.0L)»(ref-22927) (Sable, Taurus, Tempo, Taurus 3.0L & Taurus 3.0L SHO)
- «SYSTEM/COMPONENT TESTS - EEC-IV (3.2L SHO)»(ref-22928) (Taurus SHO)
- «SYSTEM/COMPONENT TESTS - EEC-IV (3.8L)»(ref-22929) (Continental, Cougar, Sable, Taurus & Thunderbird 3.8L)
- «SYSTEM/COMPONENT TESTS - EEC-V»(ref-22914) (Mustang 3.8L)
HIGH TENSION WIRE RESISTANCE
| Application (1) | Ohms |
|---|
| 3.0L, 3.8L | 7000 Per Foot |
| (1) Distributorless systems are 30,000 ohms total per wire. |
| (1) | Distributorless systems are 30,000 ohms total per wire. |
HIGH TENSION WIRE RESISTANCE
SPARK PLUGS
| Application | Motorcraft No. |
|---|
| 2.5L | AGSP-33C |
| 3.0L Flexible Fuel | AWSF-32C |
| 3.0L Except Flexible Fuel & SHO | AWSF-32P |
| 3.0L SHO & 3.2L SHO | AGSP-32PP |
| 3.8L Except SC |
| California | AWSF-44P |
| Federal | AWSF-44C |
| 3.8L SC | AWSF-34P |
| Application | Gap: In. (mm) | Torque: Ft. Lbs. (N.m) |
|---|
| 2.5L | .039-.043 (0.99-1.09) | 11-16 (15-22) |
| 3.0L Except SHO | .044 (1.12) | 10 (14) |
| 3.0L SHO & 3.2L SHO | .042-.046 (1.07-1.17) | 16-20 (22-27) |
| 3.8L | .052-.056 (1.32-1.42) | 11 (15) |
SPARK PLUG SPECIFICATIONS
Firing Order & Timing Marks (2.5L). Scheme 6
Scheme 6: Firing Order & Timing Marks (2.5L)
Firing Order & Timing Marks (3.0L - Except SHO). Scheme 7
Scheme 7: Firing Order & Timing Marks (3.0L - Except SHO)
Firing Order & Timing Marks (3.0L SHO & 3.2L SHO). Scheme 8
Scheme 8: Firing Order & Timing Marks (3.0L SHO & 3.2L SHO)
Scheme 9
Scheme 9: Spark Plug Wire Routing (3.0L SHO & 3.2L SHO)
Firing Order & Timing Marks (3.8L - Continental, Sable & Taurus). Scheme 10
Scheme 10: Firing Order & Timing Marks (3.8L - Continental, Sable & Taurus)
Firing Order & Timing Marks (3.8L - Mustang). Scheme 11
Scheme 11: Firing Order & Timing Marks (3.8L - Mustang)
Scheme 12
Scheme 12: Spark Plug Wire Routing (3.8L - Mustang)
Firing Order & Timing Marks (3.8L - Cougar & Thunderbird, Except Supercharged). Scheme 13
Scheme 13: Firing Order & Timing Marks (3.8L - Cougar & Thunderbird, Except Supercharged)
Firing Order & Timing Marks (3.8L - Thunderbird Supercharged). Scheme 14
Scheme 14: Firing Order & Timing Marks (3.8L - Thunderbird Supercharged)
Scheme 15
Scheme 15: Spark Plug Wire Routing (3.8L - Thunderbird Supercharged)
IGNITION TIMING
| Application | Degrees BTDC @ Idle |
|---|
| 2.5L | (1) 9-11 |
| 3.0L (All) & 3.2L SHO | (2) 10 |
| 3.8L | (2) 10 |
| (1) With STI terminal grounded. (2) Disconnect single in-line SPOUT connector or remove shorting bar from double-wire SPOUT connector. |
| (1) | With STI terminal grounded. |
| (2) | Disconnect single in-line SPOUT connector or remove shorting bar from double-wire SPOUT connector. |
FUEL PUMP
Note. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article.
IDLE SPEED & MIXTURE
Note. Idle mixture is not adjustable. If idle mixture is incorrect, see appropriate TESTS W/CODES article in the ENGINE PERFORMANCE section. Refer to the following menu
- «TESTS W/CODES - EEC 2.5L»(ref-22894) (Probe 2.5L)
- «TESTS W/CODES - EEC-IV (3.0L)»(ref-22895) (Sable, Taurus, Taurus 3.0L SHO, Tempo & Topaz)
- «TESTS W/CODES - EEC-IV (3.2L SHO)»(ref-22896) (Taurus 3.2L SHO)
- «TESTS W/CODES - EEC-IV (3.8L)»(ref-22897) (Continental, Cougar, Mustang, Sable, Taurus & Thunderbird 3.8L)
- «TESTS W/CODES - EEC-V (3.8L)»(ref-22898) (for Mustang 3.8L)
| Model | RPM |
|---|
| 3.0L (Except SHO) | (2) |
| 3.0L SHO | 770-850 |
| 3.2L SHO | (1) 720-780 |
| 3.8L | (2) |
| (1) Idle speed is not adjustable. (2) Information is not available. |
| (1) | Idle speed is not adjustable. |
| (2) | Information is not available. |
IDLE SPEED SPECIFICATIONS
THROTTLE POSITION (TP) SENSOR
| Throttle Angle | (1) Volts |
|---|
| 0° | .50 |
| 10° | .97 |
| 20° | 1.44 |
| 30° | 1.90 |
| 40° | 2.37 |
| 50° | 2.84 |
| 60° | 3.31 |
| 70° | 3.78 |
| 80° | 4.24 |
| (1) Values may vary by 15 percent. |
| (1) | Values may vary by 15 percent. |
