Diesel Fuel System - Winter Diesel Fuel Additive Info.

Condition

Diesel Fuel, Cold Weather Conditioning for Driving at Temperatures below 0 degree C (32 degree F)
Poor diesel engine performance in ambient air temperatures below freezing (0 degree C ( 32 degree F)) may be caused by a condition known as diesel fuel clouding (gelling/waxing), a result of improperly winterized/conditioned diesel fuel provided by fuel suppliers.

Water contamination in diesel fuel can also cause similar conditions as the result of ice accumulation in the vehicle's fuel system.





20 07 01 Jan. 18, 2007 2001847 Supersedes T. B. Group 20 number 03-01 due to additional models and model years.

Technical Background
Cold weather diesel fuel Conditioner available.

Production Solution
No production change required.

Service

WARNING:
When working on ANY fuel system, ALWAYS read and follow Repair Manual CAUTIONS and WARNINGS !





To help prevent this condition from occurring, recommend to diesel powered vehicle owners that a quality diesel fuel winterizer/conditioner be used during winter months. Volkswagen of America, Inc. recommends using Stanadyne(TM) One Shot Performance Formula All Season Diesel Fuel Conditioner in the correct amount per tank full of fuel as listed below.

NOTE:
DO NOT use diesel fuel additives containing alcohol! Alcohol WILL NOT address fuel clouding (gelling/waxing) conditions. Using alcohol will damage the diesel injection pump.

- Add 8 oz. (235ml.) per 15 gallons (60ltr) diesel fuel of Stanadyne One Shot Performance Formula All Season Diesel Fuel Conditioner directly to fuel tank. Part No: ZVW340002.

NOTE:
For vehicles which will be operated at temperatures below -30 degree C (-22 degree F) add 12oz. (355ml.) per 15 gallons (60 ltr) of diesel fuel.

To determine if condition is due to diesel fuel clouding (fuel gelling/waxing) or water (ice/ moisture) contamination in the fuel system tank, lines, fuel filter) use the following:

Diesel fuel system, inspecting condition





- Check fuel system for small air leaks i.e. air bubbles in:

Fuel filter (insertion hole of regulator valve out of round)

Fuel lines

- Repair or replace as necessary.

Fuel with water contamination:
If fuel is contaminated with water (ice/moisture):
- Drain fuel system (tank, lines).
- Replace fuel filter.
- Add 8 oz. (235ml.) per 15 gallons (60ltr) diesel fuel of Stanadyne One Shot Performance Formula All Season Diesel Fuel Conditioner directly to fuel tank. Part No: ZVW340002.
- Close fuel system, reinstall fuel gauge sensor/fuel reservoir assembly.
- Add new clean diesel fuel from a known winterized source.

NOTE:
Fuel contamination, which includes water accumulation is not covered by Warranty.

Fuel, clouding
If fuel is clouding (gelling/waxing):
- Close fuel system, reinstall fuel gauge sensor/fuel reservoir assembly
- Allow vehicle to sit indoors long enough to bring fuel temperature up to approx. 13 degree C (55 degree F) (may take several hours).
- Remove fuel gauge sensor/fuel reservoir assembly again and observe fuel condition again.

Cloudiness (gelling/waxing) should no longer be seen.
- Add the correct amount (8 oz. (235ml.) per 15 gallons (60ltr) of diesel fuel) of Stanadyne(TM) One Shot Performance Formula All Season Diesel Fuel Conditioner directly to fuel tank.

NOTE: For vehicles which will be operated at temperatures below -30 degree C (-22 degree F) add 12oz. (355ml.) per 15 gallons (60 ltr) of diesel fuel.
Fuel conditioning is a result of improperly winterized/conditioned diesel fuel provided by fuel suppliers, and is not covered by Warranty.

- Thoroughly mix the additive with the fuel.

Additive, ensuring distribution throughout fuel system
- Start and run engine approx. 10 minutes to ensure conditioned fuel has circulated throughout the system.

Warranty
Information only.

Tip: Fuel contamination which includes water accumulation is not covered by Warranty.
Fuel clouding (gelling/waxing) is a result of improperly winterized/conditioned diesel fuel provided by fuel suppliers and is not covered by Warranty.

- Review with your customer, the necessity of obtaining fuel from a known winterized source during colder weather.

Required Parts and Tools





No Special Tools required.