I OWN A 2.5 TDI Touareg with 107k miles -- 2005 year.
Over the last six months the sump oil level has increased from full to 1/4 of an inch (5mmapprox). Does anyone have an answer as to what the problem could be?
What do you mean INCREASED from full to 1/4? That would be a reduction.
Also depends when you measure it. Just after turning the motor off, the level
will be lower than if it sat for a day.
I have been doing oil changes for 30 years, and only owning a Volkswagen
have I ever taken more out than I put in... I had a '13TDI, changed the oil
the same amount EVERY time, and then once I took 7 quarts out of it...
However, I usually heat the car up so the oil comes out faster, and this
one instance, I waited a day, and got all that oil out of it...
Thanks for your reply, 2013tdi, sorry I did not make myself very clear. I meant the sump/pan oil level has risen from the full level on the dipstick. I have had a couple of suggestions why this has happened :- the DFP (diesel particulate filter) is not regenerating properly and extra diesel is being pumped into the sump, AND/OR the injector seals have failed allowing fuel into the sump. It is going to a diesel specialist tomorrow for diagnostic investigation -- I will post when I get the answer. -- looks expensive which ever way it is!
You would clearly smell the diesel fuel in the oil, and that has nothing do do
with the DPF, which a 2005 Touareg Diesel DOES NOT have. Cars and light trucks
were not made with DPFs till 2009, when it became mandatory. If you are not
in the USA and have a DPF because you're in Canada or Europe, well, you didn't
mention that either. Other than that, if it's a 2008 and lower, there is no
DPF on it in the USA.
Faulty compression rings would cause diesel to get into the sump through
the pistons. A clogging DPF would rob you of horse power, and overall
temperatures would increase. Your DPF light would also be on all the time
if it cannot REGEN, you did not mention a DPF light, so you don't have a DPF.
When it gets bad, as you say it is, your glow plug, check engine light, AND
DPF light would be on.
Injector seals would have fuel blowing out on to the motor, not into the
SUMP. The seal is to retain compression because the injectors are
right in the cylinders, not the head. Without the seals, there would be
no compression. SO, faulty seals = fuel in the engine compartment, you'd
smell that too.
LEAKING fuel injectors, when the car is OFF; the fuel will get into the sump.
This is not SEALS, this is the fuel injector(s) not closing when the car is off.
Also, if they are bad, and are not closing properly while running, the excess
fuel will be seen as black smoke out the exhaust. Then again, if you have a
DPF you would not see it... THEN, the excess fuel will keep the DPF in a constant
active REGEN mode, as when REGEN is active, diesel fuel is injected into the
cylinders on the exhaust stroke, so, your DPF would burn out eventually, but before
that would get extremely hot, and so would your turbo; you'd get a warning for
that too, then the Glow Plug light would come on, and you'd be in limp mode with
hardly any boost.
Many thanks again 2013Tdi, please accept my apologies for delay replying, had two weeks holiday the day after a visit to the "diesel diagnostic" people.
You are quite right, my vehicle does not have a DPF, so that is one leak option out of the way.
The diagnostic electronic tool did not show up any faults, and as you say there was no smell of diesel in the sump oil, so they changed the oil and filter, and told me to keep a watchful eye on the level over the next six months , and if the same thing happens, come back and they will examine the injectors and seals. So, 462 miles later, after the car working hard and pulling and running well towing a caravan, the oil level remained on the full mark on the dipstick.
Thank you for taking the trouble to give a very complete answer, very much appreciated.