ENGINE COMPRESSION
Check engine compression with engine at normal operating temperature, all spark plugs removed (on dual plugs, remove exhaust side only), and throttle wide open. Ensure crankcase is full and oil is of correct viscosity. With compression gauge installed, use remote starter switch to crank engine. Crank engine at least 5 revolutions, 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. No cylinder compression reading should be less than 100 psi (7 kg/cm 2 ).
| Application | Compression Ratio |
|---|---|
| 5.0L | 9.0:1 |
COMPRESSION RATIO SPECIFICATIONS
VALVE CLEARANCE
Note. Vehicles are equipped with hydraulic valve lifters; valve adjustment is not required. If valves are noisy or incorrect clearance is suspected, worn components are indicated. Check collapsed valve lifter clearance. See appropriate article in the ENGINES section.
HIGH TENSION WIRE RESISTANCE
| Application | Ohms |
|---|---|
| 5.0L | 7000 Per Foot |
HIGH TENSION WIRE RESISTANCE
SPARK PLUGS
Note. If reusing originally installed spark plugs, reinstall them in original position. Some cylinders use platinum ground electrodes and some cylinders use platinum positive electrodes. Replacement platinum spark plugs are double platinum electrode spark plugs and are used for all cylinders.
| Application | Motorcraft No. |
|---|---|
| 5.0L | AWSF-32EE |
SPARK PLUG TYPE
| Application | Gap In. (mm) | Torque Ft. Lbs. (N.m) |
|---|---|---|
| 5.0L | .052-.056 (1.32-1.42) | 7-14 (9-20) |
SPARK PLUG SPECIFICATIONS
FIRING ORDER & TIMING MARKS
Note. Use illustrations for firing order and timing marks. (Scheme 5)
Identifying Firing Order & Timing Marks. Scheme 5
Scheme 6
IGNITION TIMING
Note. Vehicles have distributorless electronic ignition; manufacturer does not recommend checking ignition timing, as faulty readings are common and timing is not adjustable.
| Application | Degrees BTDC |
|---|---|
| 5.0L | (1) 8-10 |
| (1) With IAC solenoid connector unplugged. | |
| (1) | With IAC solenoid connector unplugged. |
BASE IGNITION TIMING
FUEL PUMP
Note. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article.
IDLE SPEED & MIXTURE
Note. Idle mixture is not adjustable. For additional information, see TESTS W/CODES - 5.0L article.
| Application | (1) (2) RPM |
|---|---|
| 5.0L | 725-775 |
| (1) Idle speed is checked with engine warm and all accessories and fan off. (2) Idle speed is computer controlled and is not adjustable. | |
| (1) | Idle speed is checked with engine warm and all accessories and fan off. |
| (2) | Idle speed is computer controlled and is not adjustable. |
IDLE RPM SPECIFICATION
THROTTLE POSITION (TP) SENSOR
Note. Throttle Position (TP) sensor is not serviceable. If TP sensor service is required, see CIRCUIT TEST DH in TESTS W/CODES - 5.0L article.
| Throttle Angle Degrees | (1) Voltage |
|---|---|
| 0 | .65 |
| 10 | .97 |
| 20 | 1.30 |
| 30 | 1.50 |
| 45 | 2.37 |
| 53 | 2.84 |
| 60 | 3.20 |
| 70 | 3.60 |
| (1) Values may vary by 15 percent. For testing, refer to CIRCUIT TEST DH in TESTS W/CODES - 5.0L article. | |
| (1) | Values may vary by 15 percent. For testing, refer to CIRCUIT TEST DH in TESTS W/CODES - 5.0L article. |
TP SENSOR OUTPUT