Engine Controls - Adjustments: Other Ford Bronco V

ENGINE MECHANICAL

Before performing any on-vehicle adjustments to fuel or ignition systems, ensure engine mechanical condition is okay.

VALVE CLEARANCE

Note. Valve cover(s) must be removed before performing valve adjustment. See appropriate article in ENGINES section for removal and installation procedures.

Initial Timing (5.0L & 5.8L)

1. Set transmission in Park or Neutral. Turn A/C and heater off. Connect inductive timing light to engine. With engine off, unplug in-line SPOUT (Yellow/Light Green wire near distributor) connector, or remove shorting bar from the double-wire SPOUT connector. Start and warm engine to normal operating temperature. DO NOT start engine with remote starter switch; use only ignition key.
2. With engine at idle speed, check/adjust initial timing to 10 degrees BTDC. Turn engine off. Reconnect the single-wire in-line SPOUT connector or reinstall shorting bar on double-wire SPOUT connector. Start engine. Verify timing advances beyond initial setting. Remove test equipment and reconnect all components.

IDLE SPEED & MIXTURE

Note. Idle mixture is not adjustable. If idle mixture is incorrect, see TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE section.

COLD (FAST) IDLE

Fast idle speed is computer controlled. Adjustment is not required.

5.0L (With E4OD) & 5.8L

1. Connect scan tester to diagnostic connector. Enter KOER self-test. A single-pulse tone indicates entry mode has been successfully entered. Observe scan tester readout.
2. If a constant tone, solid light, or STO LO is displayed, base idle speed is within range and adjustment is not necessary. Exit self-test.
3. If a beeping tone, flashing light, or STO LO display flashes at 8 Hz, TPS is out of range and adjustment is required. Perform adjustment and repeat test.
4. If a beeping tone, flashing light, or STO LO display flashes at 4 Hz, base idle speed is too high. Go to step 7).
5. If a beeping tone, flashing light, or STO LO display flashes at one Hz, base idle speed is too low. Go to next step.
6. DO NOT clean throttle body. Check throttle plate for presence of throttle plate orifice plug. (Схема №1) If there is no plug, rotate throttle return screw CLOCKWISE only to adjust idle speed until conditions in step 2) are obtained. If there is a plug from previous service, remove plug and rotate screw in either direction to obtain conditions in step 2). After adjustment, screw MUST be in contact with throttle lever pad.
7. If idle speed is too high, turn engine off. Using tape, block off orifice in throttle plate. If orifice is already plugged, go to next step. On mass airflow engines, reconnect air cleaner hose. On all models, restart engine and check idle speed. If engine stalls, crack throttle plate open with throttle plate stop screw. If idle speed is still too high, go to next step. If idle speed drops to specification or drops lower than specification, go to step 9).
8. Perform KOEO self-test. If fault codes are present, repair as necessary. See «TESTS W/CODES - EEC-IV»(ref-22952) article in the ENGINE PERFORMANCE section. If TPS fault code exists, check for proper TPS output. See THROTTLE POSITION SENSOR (TPS). Ensure adjustment screw is in contact with lever pad. If fault codes do not exist, proceed to «TESTS W/O CODES»(ref-22970) article in the ENGINE PERFORMANCE section.
9. Turn ignition off. Remove air cleaner hose. Remove tape from throttle plate orifice. Select correct color plug for orifice. Plugs are available in Throttle Plate Plug Kit (FOPE-9F652-AA).
10. Reconnect air cleaner hose. Start engine. Recheck idle speed. If idle speed is not within specification, turn adjuster screw CLOCKWISE to obtain correct idle speed. After adjustment, screw MUST be in contact with throttle lever pad.
11. On all models, perform a KOEO self-test to verify TPS fault code does not exist. Move throttle plate to verify it is not stuck in bore and linkage is not keeping throttle from closing. On models with automatic overdrive transmissions, check throttle valve pressure adjustment.

THROTTLE POSITION (TP) SENSOR

Note. Throttle Position (TP) Sensor on gasoline engines is not adjustable. Replace TP sensor is not within specification.

1. Unplug PCM 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair as necessary. Connect Breakout Box (T83L-50-EEC-IV) and reconnect PCM to breakout box. Connect digital voltmeter positive lead to pin No. 47 and negative lead to pin No. 46. Turn ignition on. Observe voltmeter while moving throttle slowly to Wide Open Throttle (WOT) position. Release throttle slowly to closed position. Voltage should change smoothly from about .6 volt at idle position, to about 4.5 volts with throttle wide open.
2. If voltage is not as specified, ensure throttle stop screw and linkage are adjusted correctly. Remove TPS and check for damaged, corroded, or misadjusted pins. If pins are okay, install sensor. Ensure sensor is seated correctly. Repeat step 1). If voltage is not as specified, perform CIRCUIT TEST DH in «TESTS W/CODES - EEC-IV»(ref-22952) article in the ENGINE PERFORMANCE section.