Hose Warm-up valve to Air filter box. Porsche 930 1983-89  ❭  99923903440

Hose – Warm-Up Valve to Air Filter 
Sold per metre

High-quality hose designed for Porsche 911 turbo (930) models from 1983 to 1989, connecting the warm-up valve (warm-up regulator) to the air filter box.

Fits:

• Porsche 911 1978-1989 3.3L Turbo (930

Diagram ref no 26

This hose plays a key role in the Bosch CIS (Continuous Injection System), supporting proper airflow and pressure regulation between the warm-up valve and intake system. It is essential for maintaining correct engine warm-up characteristics and stable fuel delivery.

Sold per metre, this hose allows for custom length replacement, making it ideal for maintenance, repair, or restoration of classic Porsche 911 Turbo fuel and intake systems. Manufactured to OEM specifications for reliable fitment and performance.

Key Features

• Hose for warm-up valve to air filter box connection
• Suitable for Porsche 911 Turbo (1983–1989)
• Part number 99923903440
• Designed for CIS fuel injection systems
• Sold per metre for custom length applications
• Flexible and durable construction
• OEM-style fit and performance

Function and Purpose

This hose is an important part of the CIS system.

It helps to:
• Connect the warm-up valve to the air intake system
• Maintain correct air and pressure balance
• Support proper engine warm-up operation
• Ensure consistent fuel delivery
• Enable stable engine performance

Why Replace Hoses

Over time, hoses can degrade due to heat and engine bay conditions.

Common issues include:
• Cracking or splitting
• Air leaks affecting engine performance
• Hardening and loss of flexibility
• Reduced efficiency of the CIS system

Replacing worn hoses ensures correct system operation and engine reliability.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99923903440

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