Replacing Manual Transmission Breather Cap Acura RSX Type S - DIY Guide

Replacing the Manual Transmission Breather Cap on an Acura RSX Type S

The Acura RSX Type S is a sporty compact car that was produced from 2002-2006. It came equipped with a high-revving 2.0L 4-cylinder engine and close-ratio 6-speed manual transmission. While the RSX Type S is a reliable vehicle, the manual transmission breather cap can become cracked or damaged over time and need replacing.

What is the Manual Transmission Breather Cap?

The manual transmission breather cap is a small plastic cover located on top of the transmission housing. It allows air flow in and out of the transmission as the gear oil expands and contracts with temperature changes. This equalizes the internal pressure and prevents seals from being pushed out.

The breather cap has a mesh filter screen inside that prevents dirt and debris from entering the transmission. Over time, this filter can become clogged, causing abnormal pressure changes inside the transmission.

Symptoms of a Bad or Clogged Breather Cap

Here are some common signs that your RSX's manual transmission breather cap needs to be replaced:

• Difficulty shifting gears
• Grinding noises, especially when shifting into reverse
• Transmission overheating due to lack of proper ventilation
• Leaking transmission fluid
• Check engine light caused by improper pressure readings

Replacing the Breather Cap - Step-by-Step Instructions

Replacing the manual transmission breather cap on an RSX takes less than 15 minutes if you have the right tools. Here is the complete process:

Items Needed:

• Replacement breather cap - Honda part #21396-P20-000
• Flat head screwdriver
• Clean shop rags

1. Raise the front of the vehicle and support securely on jack stands.
2. Locate the transmission breather cap on top of the transmission housing near the clutch slave cylinder.
3. Use a flat head screwdriver to gently pry up on the edge of the cap to pop it off.
4. Inspect the old breather cap and look for cracks or a clogged filter screen.
5. Clean any dirt or debris from the breather opening on the transmission housing.
6. Install the new breather cap by gently pushing down until it clicks into place.
7. Lower vehicle safely back to the ground.
8. Road test the car and confirm normal transmission operation.

How Often Should the Breather Cap Be Replaced?

Honda recommends inspecting the manual transmission breather cap every 30,000 miles. However, the interval can vary greatly depending on driving conditions and climate.

If you regularly drive in dusty environments or on gravel roads, more frequent inspection is a good idea. Any time you replace the transmission fluid is also an excellent time to swap out the breather cap as preventative maintenance.

Where to Buy a Genuine Honda Breather Cap

To ensure proper fit and function, always replace your RSX's breather cap with a genuine Honda part. The OEM part number is 21396-P20-000.

Genuine Honda parts are available from the parts counter at any Acura or Honda dealership. Many online retailers like Amazon and Honda Parts Now also carry this breather cap.

Aftermarket versions are available as well but may not provide the exact same quality and durability as the factory component.

Tips for Changing the Breather Cap

• Use a plastic pry tool instead of a screwdriver to avoid cracking the breather neck.
• Wear safety glasses in case the old cap breaks apart during removal.
• Do not overtighten the new cap - just press down gently until it clicks.
• Dispose of used motor oil and transmission fluid properly.

Conclusion

Replacing the manual transmission breather cap is an easy and inexpensive repair on the Acura RSX Type S. Simply pop off the old cap, clean the mounting surface, and install a new genuine Honda replacement part. This prevents transmission issues and ensures long gearbox life.

With basic hand tools and about 15 minutes, you can swap the breather cap yourself and get back to enjoying your RSX Type S. Be sure to use Honda part #21396-P20-000 for proper fit and function.

FAQs

What are the symptoms of a bad transmission breather cap?

Symptoms can include difficulty shifting gears, grinding noises, transmission overheating, fluid leaks, and check engine lights due to improper pressure readings.

How often should I replace the breather cap?

Honda recommends inspecting the breather cap every 30,000 miles and replacing as needed. More frequent replacement may be required if driving in dusty conditions regularly.

Can I just clean the old breather cap instead of replacing it?

It's not recommended. The plastic caps become brittle and prone to cracking over time. Replacing the cap ensures you have a new filter screen and proper sealing.

Where can I buy the correct replacement breather cap?

The best place to buy a genuine Honda replacement is from a Honda or Acura dealer parts counter. Many online retailers also carry the OEM part #21396-P20-000.

Is this a difficult DIY repair?

No, replacing the breather cap is very simple and can be done in under 15 minutes with basic hand tools and mechanical ability.