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 of 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 |
|---|---|
| 5.0L | 9.0:1 |
COMPRESSION RATIO SPECIFICATIONS
VALVE CLEARANCE
Note. 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) |
|---|---|
| Allowable | .098-.198 (2.49-5.03) |
| Preferred | .123-.146 (3.12-3.71) |
COLLAPSED VALVE LIFTER CLEARANCE
IGNITION COIL
| Application | Primary (Ohms) | Secondary (Ohms) |
|---|---|---|
| Distributorless Systems | (1) | (1) * |
| Distributor Systems | 0.8-1.6 | 8000-11,500 |
| (1) Resistance value is not available. For testing, see IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - EEC-IV (5.0L) article in the ENGINE PERFORMANCE section. | ||
| (1) | Resistance value is not available. For testing, see IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS - EEC-IV (5.0L) article in the ENGINE PERFORMANCE section. |
IGNITION COIL RESISTANCE
HIGH TENSION WIRE RESISTANCE
| Application (1) | Ohms |
|---|---|
| 5.0L | 7000 Per Foot |
| (1) On distributorless systems, high tension wire resistance is 30,000 ohms max. entire wire. | |
| (1) | On distributorless systems, high tension wire resistance is 30,000 ohms max. entire wire. |
HIGH TENSION WIRE RESISTANCE
SPARK PLUGS
| Application | Motorcraft No. |
|---|---|
| 5.0L | (1) ASF-42C |
| (1) For Cobra models, use AWSF-32C. | |
| (1) | For Cobra models, use AWSF-32C. |
SPARK PLUG TYPE
| Application | Gap: In. (mm) | Torque: Ft. Lbs. (N.m) |
|---|---|---|
| 5.0L | .054 (1.37) | 15 (20) |
SPARK PLUG SPECIFICATIONS
Firing Order & Timing Marks. Scheme 7
IGNITION TIMING
| Application | Degrees BTDC @ Idle |
|---|---|
| 5.0L | (1) 10 |
| (1) Disconnect single in-line SPOUT connector, or remove shorting bar from double-wire SPOUT connector. | |
| (1) | Disconnect single in-line SPOUT connector, or remove shorting bar from double-wire SPOUT connector. |
BASE IGNITION TIMING
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 TESTS W/CODES - EEC-IV (5.0L) article in the ENGINE PERFORMANCE section.
| Model | RPM |
|---|---|
| A/T | 625 |
| M/T | 675 |
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. |
TP SENSOR SPECIFICATIONS