Denso Suction Control Valve 294200-2750 2942002750 8-98145501-1 For ISUZU NPR75 NQR90 FSR90 4HK1 4JJ1 4JK1 & Hitachi ZX120-3 — OEM Fuel Pressure Regulator

The Suction Control Valve (SCV) with Denso OEM number 294200-2750 (also listed as 2942002750) is a verified OEM-grade direct replacement for a wide range of ISUZU diesel engines, including the 4HK1, 4JJ1, 4JK1, and 6HK1. Manufactured by Denso to stringent OEM specifications, this fuel pressure regulator valve is a critical component of the common rail fuel system.

It is mounted on the HP3 high-pressure fuel pump and is responsible for precisely controlling the volume of fuel entering the pump's plunger chamber. By regulating the fuel suction volume, the SCV maintains stable common rail pressure under all operating conditions, ensuring optimal injector performance, smooth engine running, and emissions compliance.

This valve is widely used in ISUZU NPR, NQR, FSR, and D-MAX trucks, as well as Hitachi ZX120-3 excavators. Manufactured in Japan by Denso, a leading global OEM supplier for diesel fuel injection systems, this SCV valve is an ideal choice for diesel repair, fuel system maintenance, and fleet service.

• OEM Specification – Verified by Denso OEM part number 294200-2750 and ISUZU cross-reference 8-98145501-1, 8-98145501-0, 8-98145484-1
• Precision Engineered – Features a 3.5mm diameter and 125 PSI working pressure – verified by multiple export trade data records
• Proven Durability – Manufactured by Denso (Japan) with a lightweight armature assembly (under 18 grams) and achieves a 10-to-90% step response time of under 28 milliseconds, ensuring precise and rapid fuel pressure control
• OEM Cross-Reference Verified – Replaces 294200-4750, 294200-9752, 8-98145501-0, 8-98145501-1, 8-98145484-1, A6860-VM09A, 9307Z509B
• Broad Compatibility – Fits ISUZU 4HK1, 4JJ1, 4JK1, 6HK1 engines in NPR, NQR, FSR, NLR, NMR, D-MAX, MU-X trucks and Hitachi ZX120-3 excavators

If your Suction Control Valve is failing, you may experience one or more of the following symptoms:

• Rough Idle or Uneven Running: Engine idles roughly with noticeable vibration or diesel knock – indicates unstable fuel rail pressure due to a sticking or worn SCV valve
• Loss of Engine Power: Significant reduction in power and acceleration, especially under load – the SCV is not delivering sufficient fuel volume to the high-pressure pump
• Hard Starting / Extended Cranking: Difficulty starting the engine, especially when cold – insufficient fuel pressure at startup
• Engine Stalling: Intermittent or unexpected stalling, particularly at low speeds or when decelerating
• Excessive Exhaust Smoke: Black smoke under load (incomplete combustion) or white smoke (unburned fuel) – indicates incorrect fuel delivery
• Poor Fuel Economy: Noticeable drop in fuel efficiency due to inefficient combustion
• Diagnostic Trouble Codes: DTCs related to fuel rail pressure, suction control valve circuit, or common rail system (e.g., P0087, P0088, P0093)

Our manufacturing and inspection processes ensure every SCV valve meets or exceeds Denso OEM standards.

• Depressurize the fuel system before starting work
• Disconnect the negative battery terminal
• CRITICAL: The common rail fuel system is highly sensitive to contaminated or poor-quality diesel fuel – always use clean, high-quality fuel and replace the fuel filter simultaneously
• Clean the area around the SCV valve and high-pressure pump to prevent contamination
• Inspect the pump inlet for debris or damage – clean or replace if necessary
• Quantity Required: 1 SCV valve per high-pressure pump

1. Depressurize the fuel system and disconnect the negative battery terminal
2. Locate the Suction Control Valve on the HP3 high-pressure fuel pump
3. Disconnect the electrical connector from the SCV valve
4. Remove the retaining bolts securing the SCV valve to the pump
5. Carefully remove the old SCV valve and its O-ring
6. Clean the mounting surface and valve bore thoroughly
7. CRITICAL: Install a new O-ring on the new SCV valve
8. CRITICAL: Lubricate the new O-ring with clean diesel fuel before installation
9. Install the new SCV valve and torque the retaining bolts to manufacturer's specified torque settings (refer to ISUZU workshop manual)
10. Reconnect the electrical connector until it clicks
11. Reconnect the battery and prime the fuel system
12. CRITICAL: Bleed air from the fuel system thoroughly to remove all air
13. Start the engine and check for fuel leaks around the SCV valve
14. Clear any diagnostic trouble codes using a scan tool

• Inspection: Every 50,000 km / 12 months. Check for rough idle, misfires, or increased fuel consumption
• Fuel Filter Replacement: Every 20,000-30,000 km – regular filter changes are the single biggest factor in SCV valve and fuel pump longevity
• Replacement: Recommended at 150,000 -200,000 km or immediately if failure symptoms appear
• Note: The SCV valve is a critical wear item on common rail fuel systems – proactive replacement is recommended during major fuel system service

• Packaging: Each SCV valve is securely packed in protective packaging (neutral box, color box, or custom brand package)
• Pack Quantity: 1 PCS
• Net Weight: Approx. 0.24 kg
• Suitable for: Wholesale distributors, diesel repair shops, fleet owners, and construction equipment service centers