2nd gen 3.0 TDI ALL Issues

To end this article I will briefly mention the injectors, DPF filter and a mysterious coolant loss, since all of these things are related to these diesel engines.

Injectors

The injectors will usually last at least approximately 200 000 km and in many cases even more than this – so they can somehow work even at 300 000 km or 400 000 km. However be ready, that they can fail after the already mentioned 200 000 km and rarely even before this mileage point. Either way at around 200 000 km it’s a good idea to at least remove them, have them tested and replace the washers+seals on them. But if you want to be on the safe side then you can also preventively replace all of them.

The most common symptoms of badly working injectors are:

• smoke from the exhaust at idle or during acceleration
• slightly fluctuating idle
• not good engine start mainly with a warmed up engine-so the engine cranks longer or the start is not smooth/fast enough
• slightly higher fuel consumption
• the engine oil level can raise as well.

But other symptoms can appear too like:

• flashing glow plug light
• check engine light
• misfires/uneven engine running
• limp mode/loss of power
• injector related fault codes
• a louder ticking/knocking noise from the faulty injectors
• engine won’t start

If you ignore any of these symptoms then you are risking a major engine damage which includes cracked or melted pistons and damaged cylinder walls.

Rarely the injectors can suddenly fail and start to leak excessive amount of fuel into the cylinder as well. This relatively rare phenomenon can easily end with a cracked or melted piston which will damage the cylinder wall as well. This translates to a major engine damage!

To prolong the lifetime of the injectors use good quality fuel, eventually good fuel additives and replace the fuel filter regularly.

Leaking injector washers/seats

Apart from the faulty injectors you can experience leaking injector washers as well – in many cases even after 100 000 km, but this issue can be easily and cheaply fixed.

The symptoms of leaking injector washers are:

• regular louder or not that loud hissing type noises from the engine mostly at idle
• exhaust smell in the interior and engine compartment will appear as well
• if the leak is bigger then you will also notice a black tar like substance coming out from the injector vent holes on the cylinder heads above the exhaust manifolds. The black tar can end up on the exhaust manifolds or on the engine mount brackets so its easy to spot this.

During replacing these washers it’s important to clean the injector ports and at the same time replace all the washers and injector seals on the other injectors as well + having the injectors tested while they are out is a very good idea too + it’s good to replace the injector bolts as well – since they can stretch

DPF

All of these engines are equipped with a DPF filter. It can last even 500 000 km, but bad injectors, incorrect engine oil, and using the car mainly on short distances are gonna reduce the lifetime of this filter significantly, since it gets clogged or even destroyed! By the way, if you are gonna use the car mainly for short distances then the DPF will not burn off correctly. The result of this will be a raising oil level and later a clogged DPF.

Newer cars can be equipped with the additional adblue emission system too – which will have additional issues mainly in the older or high mileage cars, but I’m not gonna investigate this any further since nobody is paying me!

Coolant loss

All of these engines can rarely experience a mysterious coolant loss. If there is no external leak and the head gasket is fine together with the cylinder head, then this coolant loss is most probably caused by the EGR cooler. Because rarely, the EGR cooler can slightly crack internally thus allowing the coolant to mix with the carbon soot in the cooler itself + it will slowly leak into the combustion chamber. This internal coolant leak is obviously not gonna help to extend the lifetime of the DPF filter for example, so check the coolant level regularly and keep this in mind!