Harley-Davidson X440 / 440X Genuine Throttle Body Assembly – HDFH16400ACZ000S – OEM EFI Intake Control Unit

If your bike is facing unstable idle, throttle hesitation, poor pickup, erratic RPM, or fueling-related rideability issues, one of the most critical EFI components to inspect is the throttle body assembly. This genuine HDFH16400ACZ000S Throttle Body Assembly is a complete OEM unit supplied in sealed packaging, making it the correct choice when a mechanic has confirmed throttle body failure or when the original unit is damaged beyond cleaning/calibration.

The throttle body is the part of the fuel-injection intake system that regulates incoming air and works with sensors to maintain correct engine response. On a premium fuel-injected platform like the Harley X440 / 440X, using a mismatched or low-grade used unit can lead to poor idling, throttle lag, or repeat workshop visits. That is exactly why this listing is positioned as a fitment-first, diagnosis-first genuine replacement.

Why buy from Under The Hood: this is not a routine consumable—it’s a high-value EFI component. We stock genuine boxed parts, pack expensive assemblies carefully, and can help you double-check the part code before dispatch so you don’t end up with an incorrect order sitting idle in your workshop.

Key Features 

• Part Number / SKU: HDFH16400ACZ000S

• Printed item name on box: THROTTLE BODY ASSEMBLY

• MRP: ₹8,510 incl. all taxes

• Genuine sealed OEM assembly, not a loose repaired/used throttle body

• Critical EFI component for air intake control and throttle response

• Best suited for bikes showing idle fluctuation, hesitation, poor pickup, or fueling irregularity after proper diagnosis

• Better long-term reliability than buying unknown-condition used EFI parts

• High-value item: ideal for customers who already have technician confirmation

• Return-prevention: buy only after part-code / VIN / existing-unit match

Compatibility Table

Caution note: This is an EFI/mechanical control part, not a casual accessory. Do not order based only on symptoms—confirm after proper diagnosis.

Variants 

• Single OEM assembly only: HDFH16400ACZ000S – Throttle Body Assembly
  No size/color/variant options shown on the label.

What’s in the Box

• 1 × Genuine Throttle Body Assembly – HDFH16400ACZ000S

Accuracy note: The outer label confirms it is a complete Throttle Body Assembly, but it does not list sub-components externally. Sell it as a sealed genuine assembly unless you have opened stock and documented the internal contents.

Installation & Maintenance Notes

• Recommended only for professional installation

• Confirm diagnosis before ordering: throttle body issues can overlap with sensor, injector, air leak, or wiring faults

• Match by VIN / EPC / old unit code before opening the seal

• After installation, the bike may require idle/throttle adaptation or ECU-related checks depending on workshop procedure

• Keep the unit sealed until fitment is confirmed to reduce high-value return disputes

FAQs 

Q1. What is HDFH16400ACZ000S?
It is a genuine Throttle Body Assembly as printed on the box label.

Q2. What does a throttle body assembly do?
It is part of the EFI intake system and controls airflow into the engine, affecting idle stability, throttle response, and overall fueling behavior.

Q3. Will this fit my Harley X440 / 440X?
Treat it as VIN/EPC confirmation required. The visible box label confirms the part identity, but not the printed model name in the photo shown.

Q4. Should I order this if my bike has pickup issues?
Only after proper diagnosis. Pickup or idle problems can also come from sensors, injector issues, air leaks, or wiring—not only the throttle body.

Q5. Is this a complete assembly or a repair part?
The box label states Throttle Body Assembly, which indicates a complete assembly-level genuine part.

Q6. Why buy genuine for a throttle body?
Because EFI components are highly fitment-sensitive. A wrong or poor-condition unit can create repeat issues and expensive workshop time loss.