Pinpoint Test A: Clutch Pedal Feels Spongy or Has Excessive Travel/Clutch Will Not Disengage
Manual Transaxle and Clutch
Pinpoint Tests
Pinpoint Test A: Clutch Pedal Feels Spongy or Has Excessive Travel/Clutch Will Not Disengage
Normal Operation
The clutch is designed to transfer the power from the engine to the transaxle, which may be either stationary (starting) or rotating at a different speed (upshifting or downshifting). The clutch is functioning correctly when both the engine and transmission are rotating at the same speed with the clutch engaged. Clutch pedal movement is transmitted by fluid pressure, which actuates the clutch release hub and bearing. The clutch release hub and bearing pushes on the spring center towards the flywheel. The diaphragm spring pivots at the fulcrum, relieving the load on the clutch pressure plate. Steel spring straps riveted in the clutch pressure plate cover pull the clutch pressure plate from the clutch disc, disengaging the engine torque from the transaxle.
This pinpoint test is intended to diagnose the following:
- Clutch pedal
- Clutch pedal pivot
- Clutch pressure plate
- Clutch disc
PINPOINT TEST A: CLUTCH PEDAL FEELS SPONGY OR HAS EXCESSIVE TRAVEL/CLUTCH WILL NOT DISENGAGE
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A1 CHECK THE FLUID LEVEL
- Check the fluid level of the clutch reservoir.
- Is the fluid level at the correct level?
Yes
GO to A2.
No
ADD brake fluid to the specified level. GO to A2.
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A2 MEASURE THE CLUTCH RESERVE
NOTE: Remove the floor mat, if equipped, to allow the clutch pedal to travel to the downstop.
- Install a cable tie to the lower clutch pedal, then attach a tape measure to the cable tie.
- Pull the tape measure up to the steering wheel. Position it through the steering wheel opening.
- Use the seam on the steering wheel as a reference point.
- Depress the clutch fully and start the vehicle.
- Shift the transmission into REVERSE, then move the shift lever forward to the position in between REVERSE and NEUTRAL. Slowly release the clutch pedal (if the vehicle creeps rearward, move the shift lever forward a little more).
- With the clutch pedal up, gently pull the shift lever toward REVERSE position. Gear clash can now be heard.
- Slowly depress the clutch pedal. Note the measurement when the gear clash stops or the shift lever slides into REVERSE.
- Depress the clutch pedal to the downstop. Note the measurement. The difference between the measurement taken when the gear clash stopped and the measurement taken at the downstop is the clutch reserve.
- Is the clutch reserve between 27 mm (1.062 in) to 38 mm (1.495 in)?
Yes
If the clutch reserve is between 27 mm (1.062 in) to 38 mm (1.495 in), the clutch hydraulic system is OK. TEST the system for normal operation.
No
REFER to Evaluation of Clutch Hydraulic System. INSTALL a new pressure plate and clutch disc. REFER to Clutch Service and Repair.
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