How to Fix Exhaust Heat Problems Caused by Corvette Closeout Panels

How to Fix Exhaust Issue

Experiencing exhaust issues in your 2020 Chevrolet Corvette can be frustrating. Common symptoms include smoke, road noise, and even excessive heat. One owner mentioned, "I wish I had purchased the smoke unit earlier to troubleshoot evap issues. The owners manual to the unit I purchased also says you can use it to find exhaust leaks."

Symptoms

Owners of the truck have reported several symptoms related to exhaust problems. These range from noticeable smoke emanating from the exhaust system to unusual road noise and vibrations. You might also experience excessive heat radiating from the exhaust components.

Some owners have described a "sizzling" sound, especially after the engine is turned off. This can indicate a leak or issue with heat dissipation in the exhaust system. Addressing these symptoms promptly can prevent further damage.

The presence of smoke, regardless of color, is a clear indication of an issue. White smoke may suggest coolant leakage, while black smoke often points to a fuel mixture problem. Blue smoke typically indicates oil burning. Pay close attention to the color and density of the smoke.

Increased road noise, especially a droning or rattling sound, can be another symptom of exhaust problems. This noise might be more noticeable at certain speeds or engine RPMs. Vibrations felt through the floorboards or steering wheel can also be related.

Most Likely Cause

Based on owner reports, a primary contributor to exhaust issues involves the closeout panels. These panels, designed to improve aerodynamics and aesthetics, can sometimes interfere with the exhaust system, leading to heat buildup or other problems.

Closeout panels that are improperly installed or damaged can restrict airflow around the exhaust components. This restriction can cause excessive heat to build up, potentially leading to damage or premature wear of exhaust parts like the muffler or even the exhaust manifold. This can also contribute to increased road noise or vibrations if the panels are contacting exhaust components.

Furthermore, if the closeout panels are made of a material that is not sufficiently heat-resistant, they can melt or warp when exposed to high exhaust temperatures. This can further restrict airflow and exacerbate the problem. It's crucial to ensure these panels are properly installed and made of appropriate materials to withstand the heat.

The design of the exhaust system itself, combined with the presence of closeout panels, can create pockets where heat accumulates. This is particularly true in areas around the muffler or catalytic converters. Regular inspection of these areas is important to identify potential issues before they escalate.

How to Diagnose

Diagnosing exhaust issues related to closeout panels requires a systematic approach. Here’s how you can do it:

1. Visual Inspection: Start by visually inspecting the exhaust system, paying close attention to the closeout panels. Look for any signs of damage, such as cracks, melting, or warping. Also, check for any gaps or misalignment between the panels and the exhaust components.

2. Smoke Test: As Varilux mentioned, using a smoke machine can be highly effective: "I wish I had purchased the smoke unit earlier to troubleshoot evap issues. The owners manual to the unit I purchased also says you can use it to find exhaust leaks.” A smoke test involves injecting smoke into the exhaust system to identify leaks. This method is especially useful for finding small leaks that might not be visible otherwise. You'll need a smoke machine designed for automotive use.

3. Listen for Leaks: With the engine running, listen carefully for any hissing or whistling sounds coming from the exhaust system. These sounds can indicate exhaust leaks, especially around joints or welds.

4. Feel for Heat: Carefully feel around the exhaust system for areas of excessive heat. Be extremely cautious to avoid burns. A non-contact infrared thermometer can be helpful for measuring surface temperatures without touching the components.

5. Check Panel Fitment: Ensure that all closeout panels are properly secured and aligned. Check for any loose fasteners or damaged mounting points. Make sure the panels are not contacting any exhaust components.

Tools Needed:

• Jack and jack stands
• Wrench set
• Screwdriver set
• Smoke machine (optional)
• Infrared thermometer (optional)
• Gloves and safety glasses

Step-by-Step Fix

Addressing exhaust issues related to closeout panels involves careful inspection and potential adjustments or replacements. Here’s a step-by-step guide:

1. Preparation: Safely lift your vehicle using a jack and secure it with jack stands. Ensure the vehicle is stable before proceeding. Allow the exhaust system to cool completely before beginning any work.

2. Inspect Closeout Panels: Examine the closeout panels for any signs of damage, such as cracks, melting, or warping. Check the panel material for signs of degradation due to excessive heat exposure.

3. Check Panel Fitment: Verify that the panels are correctly installed and aligned. Look for any loose fasteners or damaged mounting points. Ensure the panels are not directly contacting the exhaust components, such as the muffler or exhaust pipes.

4. Adjust Panel Position: If the panels are misaligned, carefully adjust their position to create adequate clearance between the panels and the exhaust system. Use shims or spacers if necessary to provide additional clearance.

5. Repair or Replace Damaged Panels: If the panels are damaged beyond repair, replace them with new panels that are designed for high-temperature applications. Ensure the replacement panels are made of a heat-resistant material.

6. Smoke Test (Optional): If you suspect exhaust leaks, perform a smoke test to pinpoint the exact location of the leaks. Inject smoke into the exhaust system and look for any smoke escaping from joints, welds, or other potential leak points.

7. Repair Exhaust Leaks: If you find any exhaust leaks, repair them by welding or replacing the damaged components. Ensure all connections are tight and secure.

8. Reassemble and Test: Once you have made the necessary adjustments or repairs, reassemble the closeout panels and lower the vehicle. Start the engine and listen for any unusual noises or vibrations. Check for any exhaust leaks or excessive heat buildup.

9. Road Test: Take the vehicle for a road test to ensure the issue is resolved. Pay attention to any changes in noise levels, vibrations, or heat radiating from the exhaust system.

As one owner shared: "I would love to swap them for a quad tip with an electronic baffle so I can have quiet stop and go driving and loud spirited driving (far away from the law and my neighbors)." (source) This highlights the importance of considering exhaust modifications to address noise and performance concerns.

Parts and Tools Needed

• Replacement closeout panels (if damaged)
• Fasteners and mounting hardware
• Shims or spacers (if needed)
• Welding equipment (if repairing exhaust leaks)
• Exhaust sealant (if needed)
• Jack and jack stands
• Wrench set
• Screwdriver set
• Smoke machine (optional)
• Infrared thermometer (optional)
• Gloves and safety glasses

Specific part numbers will vary depending on the exact model and year of your vehicle. Consult your local parts dealer for the correct part numbers.

Real Owner Costs

The cost of addressing exhaust issues related to closeout panels can vary significantly depending on the severity of the problem and whether you choose to perform the repairs yourself or take it to a professional mechanic.

DIY Repair:

• Replacement closeout panels: $50 - $200 (depending on the material and brand)
• Fasteners and mounting hardware: $10 - $30
• Shims or spacers: $5 - $15
• Smoke machine rental: $50 - $100 (if needed)

Total DIY cost: $65 - $345

Professional Repair:

• Diagnostic fee: $75 - $150
• Replacement closeout panels: $100 - $300
• Labor: $100 - $500 (depending on the complexity of the job)

Total professional repair cost: $275 - $950

As Varilux mentioned about a smoke machine: "For now, it's looking like a very well spent $100. Here's a link to the particular device I purchased- it's pretty simple to operate and comes with everything you need (whoops, looks like it was a little more than 100- still a good buy IMO at $129- I went for the version with a built in air pump)." (source) This shows that investing in diagnostic tools can save money in the long run.

Example 1:

One owner reported spending $150 on replacement closeout panels and $50 on fasteners, performing the work themselves. The total cost was $200.

Example 2:

Another owner took their vehicle to a mechanic, who charged $100 for a diagnostic fee, $200 for replacement panels, and $300 for labor. The total cost was $600.

Prevention

Preventing exhaust issues related to closeout panels involves regular maintenance and careful attention to detail. Here are some tips:

• Regular Inspection: Inspect the closeout panels and exhaust system regularly for any signs of damage or misalignment.

• Proper Installation: Ensure that the closeout panels are properly installed and aligned according to the manufacturer's specifications.

• Heat-Resistant Materials: Use closeout panels made of heat-resistant materials to prevent melting or warping.

• Avoid Contact: Ensure that the closeout panels are not in direct contact with the exhaust components.

• Proper Ventilation: Ensure that there is adequate ventilation around the exhaust system to prevent excessive heat buildup.

• Professional Maintenance: Have the exhaust system professionally inspected and maintained regularly.

What Owners Say

Real experiences from CHEVROLET owners:

Success Stories

"Quote: Originally Posted by knewblewkorvette Even after hitting it with my purse , I still couldn't get my 98's cap to loosen. So out came the channel locks, that did the trick. if swinging my purse harder don't work, an oil filter wrench will Quote: Originally Posted by Kubs I washed it today." — _zebra (source)

"So out came the channel locks, that did the trick. if swinging my purse harder don't work, an oil filter wrench will Quote: Originally Posted by Kubs I washed it today." — _zebra (source)

Owner Experiences

"Turns out after repeated order mishaps I have three of the RPI rear plate covers now. Electron blue, painted/cleared black, and out of nowhere long after the order issues were resolved a third one showed up this weekend which is a flat black." — Tusc (source)

"I don't trust someone flashing dyno sheets at me without knowing firm details, but it claims higher curve across the mean vs our usual setups. It is done in Titanium and domestically so the price is ridiculous." — Tusc (source)

"Aside from the synchro going the transmission which was removed had always felt as heavy as it apparently was. This 70k mile drop-in feels brand new by comparison and if someone told me it had been upgraded I would be inclined to believe them based on the range of improvement." — Tusc (source)

Lessons Learned

⚠️ "I always try to sell here on the Forum first, but more often I sell the parts either locally or on the auction site. Just so many scams to watch out for on the social sites." — MSG C5 (source)

⚠️ "I wish I had purchased the smoke unit earlier to troubleshoot evap issues. The owners manual to the unit I purchased also says you can use it to find exhaust leaks." — Varilux (source)

⚠️ "Just for good measure I sourced a GSS350 Walbro/TI pump 350lph in case the Racetronix unit doesn't show up in time. I still have the option to modify my stock plastic bucket with the Walbro pump." — smitty2919 (source)

Pro Tips from Owners

💡 "They look very similar to motorcycle exhausts. I would love to swap them for a quad tip with an electronic baffle so I can have quiet stop and go driving and loud spirited driving (far away from the law and my neighbors)." — Swollgineer (source)

💡 "I would love to swap them for a quad tip with an electronic baffle so I can have quiet stop and go driving and loud spirited driving (far away from the law and my neighbors)." — Swollgineer (source)

Real Repair Costs

"For now, it's looking like a very well spent $100. Here's a link to the particular device I purchased- it's pretty simple to operate and comes with everything you need (whoops, looks like it was a little more than 100- still a good buy IMO at $129- I went for the version with a built in air pump). https://www.amazon.com/dp/B0B2JV8YDP?psc=1&ref=ppx_yo2ov_dt_b_product_details https://www.amazon.com/dp/B0B2JV8YDP?psc=1&ref=ppx_yo2ov_dt_b_product_details" — Varilux (source)

FAQ

Q: How long does it take to fix exhaust issues related to closeout panels?

A: The repair time can vary depending on the severity of the problem and whether you are performing the work yourself or taking it to a professional mechanic. DIY repairs can take anywhere from 2-4 hours, while professional repairs may take 1-3 hours.

Q: Can I drive with exhaust issues related to closeout panels?

A: Driving with exhaust issues is not recommended, as it can lead to further damage to the exhaust system and potentially pose a safety risk. Excessive heat buildup can damage other components and increase the risk of fire.

Q: Is this a common issue on the 2020 Chevrolet Corvette?

A: While not extremely common, exhaust issues related to closeout panels can occur on the truck, particularly if the panels are not properly installed or maintained. Regular inspection and maintenance can help prevent these issues.

Q: DIY vs mechanic - what's recommended?

A: If you have experience working on exhaust systems and are comfortable performing the repairs yourself, a DIY approach can save you money. However, if you are not familiar with exhaust systems or are unsure about any aspect of the repair, it is best to take it to a professional mechanic.