Audi A4 B6/B7 1.9 TDI - Tandem Pump refurbishing - seal kit - part number location - VW Passat B5.5

Tandem Pump

The beating heart of the Pump Duse Diesel engine producing reliable high pressure fuel to the high pressure injectors.

This video is specific to this model Tandem Pump that said however will be useful to the refurbishing process of any VAG ( Volkswagen Audi Group ) Tandem Pump found on PD engines.

mostly covering PD engines from the 90's to the middle late 2000's before common rail diesels were found to be more polar bear friendly and discontinued even though arguably the PD engine is one of the best & reliable Diesel engines ever made by VAG.

The Tandem pump named because it has 2 uses 1x providing servo vacuum assistance for the vehicles braking system ( the nice soft feeling when you exert pressure on the brake pedal aiding braking ) and 2x Diesel fuel pumped to the injectors via the fuel filter.

Common problems typically on high mileage engines

1. springs inside snapping leading to no servo vacuum and a hard brake pedal - or the car not starting - no Diesel to the injectors vua fuel filter.

2. Diesel leaks

3. Diesel in oil - again due to seals failing

PRO'S - very sturdy design so a new gasket seal kit will most likely fix the problem/s.

The pump shown is from a September 2003 model now with just over 150,000 miles the part number is also shown in this video.

Spring snapping tends to lean towards the over 200,000 miles range but can happen earlier and this all depends on how the car is used and driven or even a possible defect with the springs internally.

Cleanliness is absolutely key to sucess using brake cleaner and clean cloths or strong paper towel clean the entire Tandem Pump. BEWARE OF FUMES FROM BRAKE CLEANER IF IN A CONFINED AREA! Use a Mask ppf3 rated and use nitrile gloves to protect hands and eye wear - brake cleaner stings!

Mounting bolts to engine
These are the only official torque settings available provided from source Haynes Manual.
Larger upper bolts 20nm
Smaller lower bolts 10nm
you may find it difficult tightening the Smaller lower bolts so may have to tighten carefully by hand - this depends on space available.

There are no details available for official Newton Metre (nm) settings for the pump itself so do be careful when tightening bolts as this is cast aluminum and you do not want to damge the threads. Also bolts will be tight coming undone so be careful when removing to avoid damaging bolt heads and or snapping them.

This is definitely worth the time and effort.

What I found was cycling the engine 4 times i.e. ignition on & off the car started first turn of the 🔑 key after the cycling process.

Ive driven the car just over 100 miles since the refurbishing of the Tandem Pump and it starts 1st turn of the key every time now and no leaks!