Camshaft Position Sensor: Service and Repair
NOTE:1. The distributor must be disassembled to replace the camshaft position sensor.
2. The camshaft position and crankshaft position sensors are replaced as an assembly.
REMOVAL
1. Disconnect battery ground cable.
2. Remove retaining clips, distributor cap and seal ring.
3. Place an alignment mark on distributor body and engine block, indicating position of distributor body in block or cylinder head. Place No. 1 cylinder to Top Dead Center of the compression stroke. Place another mark on distributor body indicating position of rotor.
4. Disconnect wiring harness from distributor lead wire.
5. Remove distributor mounting nut, then the distributor assembly from engine.
DISASSEMBLY
1. Lightly clamp the distributor in a vise equipped with soft jaws.
2. Pull off the rotor from the rotor shaft.
3. Remove the packing rubber, lift off the cover.
4. Remove the disc and spacer. Observe which side of the disc is the top, for future reassembly.
5. Disconnect the lead wire connector.
6. Lift off the plate and unit by removing the three mounting screws.
7. Remove the shaft bearing tightening screws.
8. Make a position identification mark on the distributor shaft (for the drive gear, to prevent 180° out of alignment, reassembly).
9. Place the drive gear on a soft base (wooden block) so that it will not be damaged.
10. Drive out the roll pin by using a pin punch, remove the distributor shaft.
11. Remove sensor assembly hold down screws.
REASSEMBLY
1. Replace sensor assembly.
2. After coating the shaft with a small amount of engine oil, insert the shaft into the distributor housing.
CAUTION: Do not use solvent or similar products.
3. Align the drive gear with the mark made at the time of disassembly, and install the gear to the distributor shaft.
4. When aligning the drive gear's mating mark to the housing's mark, be sure that the notch "A" at the rotor end of the shaft is in the position shown. If no errors where made in either the marking or alignment procedures the pin holes should align properly. Drive in a new roll pin, insuring that the slit in the pin is at a 90° to the distributor shaft.
5. Install the spacer on the distributor shaft.
6. Insert the disc into the sensor assembly of the pick up unit assembly insuring the proper alignment with the notch on the spacer.
NOTE: Take care to install the disc with the correct side to the top as was observed during disassembly. Insure that the disc is clean and that the disc's slits are clear of any foreign matter.
7. Install the rotor shaft and its retaining screw.
8. Install the cover so that the cover's indentation "A" is aligned with the housing's notch "B".
INSTALLATION
1. Turn the crankshaft so that the No.1 cylinder is at top dead center.
2. Align the distributor housing and gear mating marks.
3. Install the distributor in the engine while aligning the groove of the distributor's installation flange with the center of the distributor installation stud. Adjust idle speed and ignition timing.
IDLE SPEED CHECK PROCEDURE
CAUTION: An improper throttle valve opening will increase exhaust gas temperature at deceleration, reducing catalyst life greatly and deteriorating exhaust gas cleaning performance. It also has an effect on fuel consumption and engine braking.
Checking Conditions
1. Engine coolant temperature is 80 to 95°C (176 to 203°F).
2. Engine lubricant temperature is over 80°C (176°F).
3. Lights, electric cooling fan, and all electrical accessories are off.
4. Transaxle in neutral ("P" or "N" range).
5. Steering wheel in the straight ahead position.
Checking Procedure
1. Install the tachometer and timing light.
2. Run the engine at curb idle speed.
3. Check the basic ignition timing and adjust if necessary. Refer to "Ignition Timing"
4. Run the engine for more than 5 seconds at 2000 to 3000 rpm.
5. Run the engine at idle for 2 minutes.
6. Read the idle speed.
Curb Idle: 700 ± 100 RPM
NOTE: Adjustment of idle speed is usually unnecessary because the idle speed control motor adjusts the idle speed.
SPEED ADJUSTING SCREW ADJUSTMENT
Adjustment Conditions
1. Engine coolant temperature is 80 to 95°C (176 to 203°F).
2. Engine lubricant temperature is over 80°C (176°F).
3. Lights, electric cooling fan, and all electrical accessories are off.
4. Transaxle in neutral ("P" or "N" range).
5. Steering wheel in the straight ahead position.
Adjustment Procedure
1. Loosen the accelerator cable.
2. Connect the tachometer.
3. Ground the terminal of the ignition timing adjusting connector.
4. Check ignition timing
5. Adjust the ignition timing if necessary
Standard Ignition Timing: 5° ± 2°
6. Turn off the ignition switch and ground the terminal 10 of the data link connector or, connect a scan tool to the data link connector.
7. Run the engine for more than 5 seconds at an engine speed of 2,000 to 3,000 RPM.
8. Run the engine at idle for 2 minutes.
9. Read the idle speed.
10. If it is not within the specified limits, adjust the speed adjusting screw.
Basic Idle Speed: 700 ± 100 RPM
11. Turn off the ignition switch and remove the ground from the ignition timing adjusting terminal and data link connector or disconnect the Scan Tool.
12. Remove the tachometer.
13. Disconnect the negative battery terminal (-) for 15 seconds or more.
14. Adjust the tension to the acceleration cable.
15. Restart the engine and keep it idling for 5 minutes or more.
NOTE: Since the fixed speed adjusting screw is adjusted at the factory, it is not necessary to adjust the fixed speed adjusting screw in most cases.