• Close-up of a 1KD Rail Relief part by Common Rail Cowboys, showing detailed metal components on a white background.
  • Close-up of a Common Rail Cowboys 1KD Rail Relief component installed on a vehicle's rail system.
1 2

Common Rail Cowboys

1KD Rail Relief

1KD Rail Relief

(1)

$262.00 NZD
$262.00 NZD
Sale Sold out

Taxes excluded. Shipping calculated at checkout.

Ships Same or Next Business Day

1KD Rail Relief Valve – 095420-0422

Aftermarket Mechanical Rail Relief (Limiter Assy, Fuel Pressure)

High-quality aftermarket replacement. Genuine Denso mechanical relief valves are no longer available.

Prefer to delete the mechanical relief entirely? Try our rail blank: MCR Rail Blank.

🔧 Suits
  • Toyota Hilux N70 / KUN26 – Euro 3 (2005–08/2006), 11-code injectors, pre EGR-cooler models
🧾 Cross-Refs & Part Numbers
  • Denso: 095420-0420, 095420-0422
  • Toyota fuel rails: 23810-0L010, 23810-0L020
🛠️ What It Does
  • Provides a mechanical over-pressure relief path on the common rail
  • Replaces leaking/weak OE valves that can cause pressure drop, surging or limp mode
  • Restores consistent commanded rail pressure when the stock valve is bleeding off
📦 In the Box
  • 1 × 1KD mechanical rail relief valve (095420-0422 pattern)

Gaskets/washers are typically re-used on the rail seat; replace if damaged.

🧰 Install Notes
  • Depressurise the fuel system per OEM procedure before removal
  • Clean the rail port and threads; torque to OEM spec
  • After fitment: prime, start, check for leaks; verify actual vs commanded rail pressure with a scan tool
  • If you run a rail blank instead of a relief, ECU limits must be calibrated appropriately
🚩 Symptoms of a Faulty Relief
  • Hard starting, rough idle, or rail pressure codes under load
  • Surging/hesitation; sudden pressure drop at higher demand
  • Black smoke from unstable fuelling
💳 Payment & 🚚 Shipping
  • Buy Now, Pay Later: Afterpay, Humm, Klarna & Zip
  • Free Express Shipping Australia-Wide — fast, trackable dispatch

❓ FAQs

Will this fit my early Hilux (no EGR cooler)?

Yes — it’s intended for Euro 3 N70/KUN26 (2005–08/2006) with 11-code injectors and no EGR cooler.

Do I need tuning after replacing the relief?

No tune is required for a like-for-like relief replacement. If you use a rail blank, your tuner must calibrate rail pressure targets and safeties.

Is this a genuine Denso part?

No — genuine Denso mechanical reliefs are discontinued. This is a high-quality aftermarket replacement built to OE-style specifications.

How do I diagnose a leaking relief?

Log commanded vs actual rail pressure under load. If actual pressure falls away prematurely and there are no pump/injector faults, the relief may be bleeding off.

View full details