Clutch pedal
Clutch pedal refers to the pedal used to operate the clutch hydraulic system in manual-transmission Pontiac Fiero models.
The clutch pedal is an important part of the Fiero clutch system. If the pedal is bent, worn, incorrectly assembled, or does not move the clutch master cylinder far enough, the clutch may not fully disengage.
Overview
Manual-transmission Fieros use a hydraulic clutch system.
When the driver presses the clutch pedal, the pedal moves the Clutch master cylinder pushrod. The master cylinder then sends hydraulic pressure through the clutch line to the Clutch slave cylinder, which operates the clutch release arm.
Although the clutch pedal is a simple part, pedal travel and pedal geometry are important. A small loss of movement at the pedal can reduce slave-cylinder travel at the transmission.
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Location
Image wanted: Photo showing the clutch pedal in a manual-transmission Pontiac Fiero, preferably showing its height compared with the brake pedal and the master cylinder pushrod/banjo connection.
The clutch pedal is located in the driver footwell, to the left of the brake pedal.
It is mounted as part of the pedal assembly under the dashboard. The pedal connects to the clutch master cylinder pushrod.
Function
The clutch pedal provides the driver's input to the clutch hydraulic system.
Basic operation:
- The driver presses the clutch pedal.
- The pedal moves the master cylinder pushrod.
- The master cylinder creates hydraulic pressure.
- Hydraulic pressure moves the slave cylinder.
- The slave cylinder moves the clutch release arm.
- The clutch disengages.
When the pedal is released, the clutch re-engages and the hydraulic system returns to its resting position.
Pedal height
Clutch pedal height is an important diagnostic clue.
If the clutch pedal sits too low, the master cylinder may not receive full travel. This can reduce slave-cylinder movement and prevent the clutch from fully disengaging.
A commonly used Fiero check is to compare the clutch pedal height with the brake pedal height. If the clutch pedal sits noticeably lower than it should, the pedal assembly, pushrod connection, and pedal condition should be inspected.
Pedal height alone does not prove the system is good, but it can help identify a travel problem.
Pedal travel
The clutch pedal must move far enough to operate the master cylinder correctly.
Reduced pedal travel can be caused by:
- Bent clutch pedal
- Worn pedal pivot
- Worn pedal bushings
- Worn pedal pin
- Incorrect pushrod connection
- Pushrod/banjo installed incorrectly
- Interference under the dashboard
- Floor mat interference
- Master cylinder mounting or pushrod problem
- Pedal not returning fully
If pedal travel is reduced, the slave cylinder may not move far enough even if the master cylinder and slave cylinder are otherwise good.
Bent clutch pedal
Bent clutch pedals are a known Fiero clutch-system topic.
A bent pedal can reduce master-cylinder travel and cause incomplete clutch release.
Possible symptoms include:
- Hard shifting
- Grinding when selecting gears
- Difficulty selecting first gear
- Difficulty selecting reverse
- Clutch engages very close to the floor
- Slave-cylinder travel is too short
- Shifting is easier with the engine off than with the engine running
A bent pedal can make the problem look like a bad master cylinder, bad slave cylinder, air in the system, or internal transmission failure.
Pedal material and replacement
Some Fiero clutch pedals have been discussed in terms of pedal material and bending.
When repairing clutch-release problems, the pedal should be inspected carefully. If the pedal is bent, cracked, worn, or otherwise damaged, replacing or repairing hydraulic parts alone may not solve the problem.
Replacement pedals or pedal assemblies should match the car and manual-transmission configuration.
Pushrod and banjo connection
The clutch master cylinder pushrod connection is often called the banjo.
The pushrod/banjo connects the clutch pedal to the clutch master cylinder. Its orientation and condition are important.
Problems in this area can include:
- Incorrect banjo orientation
- Worn banjo hole
- Worn pedal pin
- Bent pushrod
- Incorrect replacement master cylinder pushrod
- Loose or damaged retaining hardware
- Pedal not returning fully
If the pushrod is installed incorrectly or the connection is worn, the master cylinder may not move through its full stroke.
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Pedal return
The clutch pedal must return fully when released.
If the pedal does not return fully, the master cylinder may not reset correctly. This can cause poor clutch operation, inconsistent pedal feel, or bleeding difficulty.
Possible causes of poor pedal return include:
- Binding pedal pivot
- Worn pedal hardware
- Weak or damaged return spring, where applicable
- Master cylinder problem
- Pushrod problem
- Interference under the dashboard
- Hydraulic system problem
Relationship to slave-cylinder travel
Clutch pedal movement affects slave-cylinder travel.
If the pedal does not move the master cylinder far enough, the slave cylinder will not move far enough at the transmission. This can cause clutch drag and shifting problems.
When diagnosing clutch-release problems, slave-cylinder travel should be checked together with clutch pedal height, pedal travel, and pedal condition.
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Common problems
Common clutch pedal problems include:
- Bent pedal
- Worn pedal pivot
- Worn pedal bushings
- Worn pedal pin
- Worn or damaged banjo connection
- Incorrect pushrod orientation
- Pedal not returning fully
- Reduced pedal travel
- Interference under the dashboard
- Previous incorrect repair
These problems can reduce clutch release even when the master cylinder, slave cylinder, and clutch assembly are in good condition.
Symptoms
Possible symptoms of clutch pedal problems include:
- Clutch pedal sits too low
- Clutch pedal feels loose
- Clutch pedal does not return fully
- Clutch engages close to the floor
- Hard shifting
- Grinding when selecting gears
- Difficulty selecting reverse
- Difficulty selecting first gear
- Insufficient slave-cylinder movement
- Shifting improves if the pedal is pulled upward
- Problem remains after bleeding the clutch
- Problem remains after replacing hydraulic parts
Diagnosis
Basic diagnostic checks include:
- Compare clutch pedal height with brake pedal height.
- Check for full pedal travel.
- Inspect the clutch pedal for bending.
- Inspect the pedal pivot and bushings.
- Inspect the pedal pin.
- Inspect the master cylinder pushrod/banjo connection.
- Verify correct pushrod orientation.
- Check whether the pedal returns fully.
- Check for interference under the dashboard.
- Measure slave-cylinder movement.
- Diagnose the hydraulic system if pedal movement appears normal.
A clutch pedal problem should be considered when the hydraulic system has been bled or repaired but the clutch still does not release fully.
Relationship to clutch bleeding
A clutch pedal problem can make bleeding seem unsuccessful.
If the pedal does not move the master cylinder far enough, the system may appear to have air in it because the slave cylinder travel remains short.
Before repeatedly bleeding the system, inspect pedal height, pedal travel, and the pushrod connection.
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Relationship to shifting problems
A clutch pedal problem can cause shifting symptoms that feel like transmission problems.
Common complaints include:
- “It shifts fine with the engine off, but not with the engine running.”
- “It grinds going into reverse.”
- “It will not go into first gear.”
- “The clutch pedal feels wrong.”
- “Bleeding did not fix it.”
- “The slave cylinder does not move far enough.”
These symptoms should be diagnosed through the clutch pedal and hydraulic system before assuming the transmission is damaged.
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Relationship to transmission type
The clutch pedal is used on manual-transmission Fieros.
Factory manual transmissions include:
The pedal is part of the vehicle's clutch control system. Other parts, such as the slave cylinder, brackets, release arm, and clutch assembly, may vary by transmission.
Service notes
When working on the clutch pedal:
- Inspect the pedal before replacing multiple hydraulic parts.
- Check pedal height and travel.
- Inspect the pushrod/banjo connection.
- Verify that the pedal returns fully.
- Check for worn pivot hardware.
- Check for interference under the dashboard.
- Measure slave-cylinder travel after repairs.
- Do not assume every clutch-release problem is caused by air in the hydraulic system.
- Do not assume every hard-shifting problem is an internal transmission failure.
Notes
The clutch pedal is easy to overlook because it is not part of the transmission itself.
On a Fiero, clutch pedal condition and travel can directly affect hydraulic movement and clutch release. A bent or worn pedal can cause persistent shifting problems even after the clutch master cylinder, slave cylinder, or clutch assembly has been replaced.