Operation CHARM: Car repair manuals for everyone.

Pinpoint Test A: Clutch Pedal Pulsation




Manual Transaxle and Clutch






Pinpoint Tests

Pinpoint Test A: Clutch Pedal Pulsation

Normal Operation

Clutch pedal feel should be smooth when disengaging and engaging the clutch. Clutch pedal movement is transmitted by hydraulic fluid pressure, which actuates the clutch release fork and bearing. The clutch release fork 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 transmission.

This pinpoint test is intended to diagnose the following:
- Clutch disc
- Clutch pressure plate
- Flywheel



PINPOINT TEST A: CLUTCH PEDAL PULSATION

-------------------------------------------------
A1 CHECK THE CLUTCH PEDAL PULSATION


- Start the engine.
- With the transmission in NEUTRAL, slowly press the clutch pedal.
- Does the clutch pedal pulsate while being pressed?

Yes
GO to A2.

No
VERIFY customer concern.

-------------------------------------------------
A2 INSPECT THE PRESSURE PLATE BOLTS


- Inspect the pressure plate-to-flywheel bolts.
- Are any of the pressure plate-to-flywheel bolts loose?

Yes
TIGHTEN or INSTALL new bolts. REFER to Clutch, M/T. TEST the system for normal operation.

No
GO to A3.

-------------------------------------------------
A3 INSPECT THE CLUTCH PRESSURE PLATE


- Remove the clutch pressure plate. Refer to Clutch, M/T.
- Inspect the clutch pressure plate for wear or damage.
- Are there any signs of damage present on the clutch pressure plate?

Yes
INSTALL a new clutch pressure plate. REFER to Clutch, M/T. TEST the system for normal operation.

No
GO to A4.

-------------------------------------------------
A4 INSPECT THE CLUTCH DISC


- Check the clutch disc for wear or damage.
- Is the clutch disc OK?

Yes
GO to A5.

No
INSTALL a new clutch disc. REFER to Clutch, M/T. TEST the system for normal operation.

-------------------------------------------------
A5 INSPECT THE FLYWHEEL


- Inspect the flywheel for wear or damage.
- Is flywheel OK?

Yes
VERIFY customer concern.

No
TIGHTEN or INSTALL a new flywheel as necessary. TEST the system for normal operation.

-------------------------------------------------