2020 Honda Accord Misfire and Idle Surge? Intake Troubleshooting

How to Fix Intake Issues

The 2020 Honda Accord is a popular vehicle, but like any car, it can experience issues over time. Some owners have reported symptoms related to the intake system, which can affect engine performance. As one owner shared, "CEL, traction control, steering wheel light lit on after plugging the battery I had to do idle relearn because of cleaning throttle body and replacing a cracked air intake hose."

Symptoms

Several symptoms might indicate an issue with the intake system in your truck. One common complaint is a noticeable engine shake or misfire. You might feel this as a vibration, especially at idle. The misfire can be intermittent, making it harder to pinpoint the problem immediately.

Some drivers have experienced surging at idle, where the engine RPMs fluctuate erratically. This can be unsettling, especially when stopped at a light or in traffic. A surge can also cause the vehicle to feel jerky or unresponsive when accelerating from a standstill.

Another reported symptom is general misfiring, which may cause the engine to run rough and lack power. Misfiring can also trigger the check engine light. The diagnostic trouble code (DTC) might be related to the fuel system. "All the lights came on at once," reported one owner.

You may also notice a decrease in fuel economy. An issue with the intake system can disrupt the air-fuel mixture, causing the engine to burn more fuel than usual. Keep an eye on your MPG and compare it to what you typically get.

Most Likely Cause

Based on owner reports, the most likely cause of these symptoms is a problem with the fuel system. This could stem from a few different components. Although we don't have specific data on the intake manifold itself failing, issues related to air intake modifications are present.

The air-fuel mixture is critical for optimal engine performance. If the fuel system is not delivering the correct amount of fuel, it can lead to a lean or rich condition. A lean condition means there is too much air and not enough fuel, while a rich condition means there is too much fuel and not enough air. Both conditions can cause misfires, rough idling, and decreased fuel economy.

An intake leak can also disrupt the air-fuel ratio, leading to similar symptoms. An intake leak means that unmetered air is entering the engine, bypassing the MAF sensor. This can cause the engine to run lean, triggering misfires and other issues.

How to Diagnose

Diagnosing intake-related problems on your truck requires a systematic approach. Here's a step-by-step process to help you pinpoint the issue:

1. Visual Inspection: Start by visually inspecting the intake system for any obvious signs of damage. Look for cracks, loose connections, or damaged hoses. Pay close attention to the air intake hose, as mentioned by one owner: "CEL, traction control, steering wheel light lit on after plugging the battery I had to do idle relearn because of cleaning throttle body and replacing a cracked air intake hose."

2. Check the MAF Sensor: The Mass Air Flow (MAF) sensor measures the amount of air entering the engine. A faulty MAF sensor can provide incorrect readings, leading to fuel mixture problems. While no owners directly reported MAF sensor failure, it is related to intake issues and can cause similar problems. Use a scan tool to check the MAF sensor readings and compare them to the specifications in your vehicle's repair manual.

3. Smoke Test for Leaks: A smoke test can help you identify any intake leaks. This involves using a smoke machine to introduce smoke into the intake system. If there are any leaks, the smoke will escape, allowing you to pinpoint the location of the leak.

4. Scan for Trouble Codes: Use an OBD-II scanner to check for any diagnostic trouble codes (DTCs). These codes can provide valuable information about the nature of the problem. Common codes related to intake issues include P0171 (System Too Lean) and P0172 (System Too Rich).

5. Check Fuel Pressure: Use a fuel pressure gauge to check the fuel pressure at the fuel rail. Low fuel pressure can indicate a problem with the fuel pump, fuel filter, or fuel pressure regulator.

Step-by-Step Fix

While the exact fix will depend on the specific issue you've identified, here are some common steps that owners have taken to address intake-related problems:

1. Replace Damaged Hoses: If you find any cracked or damaged hoses, replace them immediately. Ensure that the new hoses are properly installed and securely fastened. As one owner replaced his cracked air intake hose, consider a new one.

2. Clean or Replace the MAF Sensor: If the MAF sensor is dirty or faulty, try cleaning it with a MAF sensor cleaner. If cleaning doesn't resolve the issue, you may need to replace the MAF sensor.

3. Address Intake Leaks: If you find any intake leaks, repair them as soon as possible. This may involve replacing a gasket, tightening a loose connection, or replacing a damaged component.

4. Fuel System Service: Addressing potential fuel system issues can be complex, so if you are not comfortable with the work, it may be best to seek professional assistance. Here are some steps:

   • Fuel Filter: Replace the fuel filter to ensure that the fuel system is getting clean fuel.
   • Fuel Pump: Check fuel pump functionality, this is also a common issue that should be addressed.
   • Fuel Injectors: Injector maintenance can often restore proper fuel system behavior and fix your fuel trim.

5. Aftermarket Intake Re-Evaluation: Some owners reported issues after installing aftermarket intakes. "So I got a kn air intake and Rv6 mid pipe and j pipe. Less than 24 hrs later, all the lights came on while idling in the parking lot," one owner reported. Consider reverting to the stock intake system to see if the problem resolves. As another owner warned: "cold air intake isn’t gonna do jack all unless you buy one and mount it into the fender well. if you don’t move it’s position it’s not gonna matter what brand you buy, it’s all gonan suck in the hot engine air regardless."

Parts and Tools Needed

Here's a list of parts and tools you may need, depending on the specific repair:

• Replacement Hoses
• MAF Sensor Cleaner
• New MAF Sensor (if needed)
• Replacement Gaskets
• Fuel Filter
• Fuel Pressure Gauge
• OBD-II Scanner
• Smoke Machine (optional)
• Basic Hand Tools (wrenches, sockets, screwdrivers)

Real Owner Costs

The cost of repairing intake issues on your truck can vary widely, depending on the nature of the problem and whether you choose to DIY or take it to a shop.

DIY Costs:

• MAF Sensor Cleaner: $10-$20
• Replacement Hoses: $20-$50
• Fuel Filter: $20-$40
• MAF Sensor: $50-$150

Professional Repair Costs:

• Diagnosis: $75-$150
• Hose Replacement: $100-$250
• MAF Sensor Replacement: $150-$300
• Intake Leak Repair: $200-$500
• Fuel System Service: $300-$800+

Prevention

While you can't always prevent intake issues from occurring, there are some steps you can take to minimize the risk:

• Regular Maintenance: Follow your vehicle's recommended maintenance schedule, including air filter replacements and fuel system services.
• Inspect Regularly: Periodically inspect the intake system for any signs of damage, such as cracks or loose connections.
• Use Quality Parts: When replacing parts, use high-quality OEM or reputable aftermarket components.
• Proper Installation: When installing aftermarket parts, follow the manufacturer's instructions carefully and ensure that all connections are secure.

What Owners Say

Real experiences from HONDA owners:

Owner Experiences

"Hey yall, so i have this 9th gen that I riced out when i was in high school that I want to de-rice. Plasti-dipped wheels (i know, the stock wheels look so much better without the dip), a spoiler, hot-air intake (💀) and a spray painted grille." — duuuhhhhhhhhhh (source)

"Plasti-dipped wheels (i know, the stock wheels look so much better without the dip), a spoiler, hot-air intake (💀) and a spray painted grille. I want to go for a lowered daily that looks clean now." — duuuhhhhhhhhhh (source)

"Got a Takeda stage 2 cold air intake and I cannot stop hitting the gas😆 really opens up at high rpm’s. CVT is limiting the fun so badly though." — -SpamCall_abuse- (source)

Lessons Learned

⚠️ "I'd start by looking at the error codes thrown. You have several warning lights." — Tiny_Structure_7 (source)

⚠️ "You have several warning lights. It looks like something funny is going on with your throttle body, or intake." — Tiny_Structure_7 (source)

Real Repair Costs

"Everyone saying ktuner but if all you're doing is intake and k-tuner that's a waste of time and you'll gain little power for like $800" — IPlayFo4 (source)

"It better to relocate the fender well. I did it to mine and I only kept the airbox and did custom tubing to pull air more directly, its easily possible with $20 max and for much better results and without using those cheap looking aluminum intake pipes." — Heavy-Cat-1524 (source)

FAQ

Here are some frequently asked questions about intake-related issues on your 2020 Honda Accord:

Q: How long does it take to fix an intake leak?

A: The time it takes to fix an intake leak can vary depending on the location and severity of the leak. A simple hose replacement may only take an hour or two, while a more complex repair involving the intake manifold could take several hours.

Q: Can I drive with an intake leak?

A: While it may be possible to drive with an intake leak, it's not recommended. An intake leak can cause engine damage and decreased fuel economy. It's best to address the issue as soon as possible.

Q: Is this a common issue on the vehicle?

A: While intake-related issues can occur on any vehicle, they are not necessarily a common problem on the 2020 Honda Accord. However, certain factors, such as age, mileage, and maintenance habits, can increase the risk.

Q: DIY vs mechanic - what's recommended?

A: Whether to DIY or take it to a mechanic depends on your skills and comfort level. Simple repairs, such as hose replacements, can often be done at home with basic tools. However, more complex repairs, such as intake manifold replacements or fuel system services, may require specialized tools and expertise.