AUDI 4G8-807-899-C Deflector

( Manufacturer Part Number: 4G8-807-899-C ), ( Part Type: Deflector ), ( Genuine Oem: Yes ), ( Manufacturer Warranty: 1 Year ), ( Universal Fitment: Direct Replacement ), ( Year: 2015 2016 2017 2018 ), ( Parts Included: Only Part Reference 5 On The Diagram Is Included )

Review AUDI Genuine Deflector fits 2015–2018

The **Audi 4G8 807 899-C Deflector** is a precision-engineered, high-performance underbody component designed exclusively for Audi vehicles equipped with the 4G8 engine family, including models like the A4, A5, A6, and Q5 with the 2.0L turbocharged four-cylinder powerplant. This deflector serves as a critical aerodynamic and thermal management solution, strategically positioned beneath the front bumper to redirect airflow away from sensitive engine bay components while simultaneously enhancing cooling efficiency and reducing drag. Crafted from durable, lightweight materials often a high-grade polymer or reinforced composite this deflector is engineered to withstand the rigors of high-speed driving, off-road excursions, and extreme weather conditions without compromising structural integrity. Its sleek, aerodynamic contours are meticulously contoured to optimize airflow dynamics, ensuring that incoming air is efficiently channeled toward critical cooling zones, such as the radiator, intercooler, and oil cooler, while minimizing turbulence and heat buildup around the turbocharger and exhaust manifolds. Beyond its aerodynamic benefits, the deflector also acts as a protective barrier, shielding vulnerable components from road debris, gravel, and minor impacts that could otherwise lead to costly damage or performance degradation. Installation is straightforward, requiring minimal modifications to the vehicle s underbody, and it seamlessly integrates with existing Audi undercarriage systems, ensuring a clean, factory-like appearance. Whether for daily driving, track use, or off-road adventures, this deflector is an indispensable upgrade for Audi enthusiasts seeking to enhance both performance and longevity of their 4G8-powered vehicles.

### Pros and Cons of Buying an Audi 4G8 807 899-C Deflector

#### **Overview**

The **Audi 4G8 807 899-C deflector** is a part of the **4G8 engine family**, specifically designed for the **Audi A4, A6, Q5, and S5 (F1) models** with the **3.0L V6 TDI engine**. This deflector is part of the **turbocharger system**, helping to manage exhaust gases and improve turbo efficiency. Below are the key advantages and disadvantages of purchasing this part.

---

### **Pros**

1. **Improved Turbo Efficiency**

The deflector helps direct exhaust gases more effectively toward the turbocharger, reducing backpressure and allowing the turbo to spool up faster. This can lead to better throttle response and power delivery, especially in low-RPM situations.

2. **Enhanced Engine Reliability**

A well-functioning deflector prevents excessive heat buildup in the exhaust system, reducing the risk of warping or cracking in the turbo housing or manifold. This can extend the lifespan of the turbocharger and related components.

3. **Better Fuel Economy (Under Certain Conditions)**

If the original deflector was damaged or clogged, replacing it with an **OEM or high-quality aftermarket version** can restore proper exhaust flow, potentially improving fuel efficiency by ensuring optimal turbo operation.

4. **Prevents Carbon Buildup**

A faulty deflector can cause uneven exhaust flow, leading to carbon deposits in the intake valves or turbo. A new deflector helps maintain clean exhaust gases, reducing the risk of carbon fouling.

5. **OEM Fitment (If Purchasing Audi-Approved Part)**

The **4G8 807 899-C** is Audi s original part number, meaning it is designed to fit perfectly without modifications. This ensures a secure installation and avoids compatibility issues.

6. **Cost-Effective Compared to Full Turbo Replacement**

Replacing just the deflector is significantly cheaper than overhauling or replacing the entire turbocharger, making it a practical solution for minor turbo-related issues.

7. **Supports Performance Modifications**

If you plan to modify your engine (e.g., adding a bigger turbo or tuning), a high-quality deflector ensures that the exhaust gases are directed optimally, maximizing the benefits of the upgrade.

8. **Easy Installation**

The deflector is relatively straightforward to replace, especially if you have basic mechanical skills. It typically requires removing the turbo and exhaust manifold, but no major disassembly is needed.

---

### **Cons**

1. **Potential for Counterfeit Parts**

The **4G8 engine family** is common in older Audi models, making it a target for counterfeit or low-quality aftermarket parts. Purchasing from an **unverified seller** could result in a poorly made deflector that fails prematurely or doesn t fit correctly.

2. **Wear and Tear Over Time**

Even an OEM deflector will degrade with high mileage or aggressive driving. If the turbo itself is worn, replacing just the deflector may not fully resolve performance issues.

3. **Requires Professional Installation (If Uncomfortable)**

While the deflector is relatively simple to replace, improper installation (e.g., not sealing properly or misaligning it) can lead to leaks or reduced efficiency. If you lack experience, hiring a mechanic may be necessary.

4. **Limited Longevity with High-Mileage Engines**

If the rest of the turbo system (e.g., bearings, seals) is degraded, replacing just the deflector may provide temporary relief but won t address deeper turbo failure. In such cases, a full turbo rebuild or replacement may be needed sooner.

5. **Cost of Replacement (If Not OEM)**

While the **OEM 4G8 807 899-C** is reliable, aftermarket alternatives may vary in quality. Some budget options might fail quickly, leading to repeated replacements and higher long-term costs.

6. **May Not Solve All Turbo-Related Issues**

If the problem stems from **turbo lag, internal turbo damage, or exhaust leaks elsewhere**, replacing the deflector alone may not fully resolve the issue. A diagnostic check is recommended before purchasing.

7. **Environmental and Noise Considerations**

Some aftermarket deflectors (especially performance-oriented ones) may alter the exhaust note, which could be undesirable if you prefer a stock sound. The **OEM deflector** maintains the original exhaust tone.

---

### **Conclusion**

The **Audi 4G8 807 899-C deflector** is a **practical and cost-effective upgrade** for owners experiencing **turbo-related issues** such as poor spool, excessive backpressure, or carbon buildup. It is particularly beneficial if:

- The original deflector is **cracked, warped, or missing**.

- You notice **reduced turbo efficiency or rough idle**.

- You plan to **modify the engine** and want to ensure optimal exhaust flow.

However, it is **not a universal fix** if the turbo itself is failing, other components (e.g., bearings, seals) may need attention. Additionally, **quality and sourcing** are critical; always purchase from a **reputable supplier** (Audi-approved parts stores, trusted aftermarket brands, or certified mechanics) to avoid counterfeit or low-quality parts.

---

### **Recommendation**

1. **Verify the Issue First**

Before buying, confirm that the deflector is indeed the problem. Symptoms like **slow turbo spool, excessive exhaust noise, or check engine lights (P0299, P0200, etc.)** may indicate a deflector or turbo issue. A **scan tool and visual inspection** can help diagnose the problem.

2. **Choose the Right Part**

- **OEM (4G8 807 899-C):** Best for reliability and fitment, but may be pricier.

- **High-Quality Aftermarket:** Brands like **Garrett, BorgWarner, or reputable Audi-specific suppliers** offer durable alternatives. Avoid no-name parts.

- **Performance-Upgraded Deflectors:** If tuning or adding a bigger turbo, consider **stainless steel or high-flow deflectors** for better heat resistance.

3. **Install Properly**

- If installing yourself, ensure the deflector is **sealed correctly** (using Audi-approved gaskets and sealant).

- If unsure, consult a **mechanic experienced with Audi turbos** to avoid installation errors.

4. **Consider a Full Turbo Inspection**

If the deflector replacement doesn t fully resolve issues, have the **turbo checked for internal wear**. A **turbo rebuild or replacement** may be needed if the turbo is failing.

5. **Maintain the Turbo System**

- Use **high-quality oil** (Audi-recommended 5W-40 or synthetic).

- Avoid **short trips and cold starts** when possible, as they contribute to turbo wear.

- Consider **turbo cleaners** (like **Bergstrom Turbo Cleaner**) to prevent carbon buildup.

### **Final Verdict**

- You have confirmed the deflector is damaged or worn.

- You want to **restore stock performance** or **prevent further turbo damage**.

- You re purchasing from a **trusted source** (OEM or high-quality aftermarket).

- The turbo itself is failing (internal damage, leaks).

- You re buying from an **unverified seller** with no return policy.

- You expect it to **completely fix turbo lag** without addressing other issues.

For most owners, the **OEM 4G8 807 899-C deflector** is the safest option due to its **proven reliability and fitment**. If budget is a concern, a **reputable aftermarket brand** (e.g., **Garrett or a trusted Audi parts supplier**) can be a good alternative. Always pair this purchase with a **thorough turbo inspection** to ensure long-term reliability.

Details:

Parts must be resalable and in the original packaging. Genuine Audi Parts. Shipping Carrier substitutions may be made at our determination in an attempt to reduce shipping cost the customer. Special Order Items are not returnable under any circumstance.

Losses or damages that occur after final delivery confirmation are not covered. Electrical parts are not returnable.

part #: 4g8807899 prices

• $49.26-$166.70

specifications ocoosys:

• for makes: Audi
• for years: 2015-2018
• mpn: 4g8-807-899-c
• part type: Deflector
• genuine oem: Yes
• manufacturer warranty: 1 Year
• universal fitment: Direct Replacement
• year: 2015 2016 2017 2018
• parts included: Only Part Reference 5 On The Diagram Is Included

seller ocoosys:

• # reviews: 6422
• city: Henderson, Nevada
• rating: 99.4%

general ocoosys:

• condition: New
• Car Truck Parts Accessories > Engine Cooling Components > Other Engine Cooling Components

payments ocoosys:

• credit card: Mastercard
• wallet: Apple-pay
• other

returns ocoosys:

• time: 30 Days
• policy: Returns Accepted
• paid by: Seller

offer ocoosys:

• started: March 28, 2026
• quantity: 1
• sold: 0
• availability: In Stock
• options: Ship-to-home

shipping ocoosys:

• cost: $24.39
• class: Standard
• type: Fixed
• service: Standard
• transit: 7-13 Days

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