Cedo21

Hi All,

I'm new to this forum.
I'm about to purchase and Audi Q7 that needs work. It's the BUG engine v6 3.0 tdi. The guy let the car sit for nearly 1.5 years and didn't drive it. Reason was because he went to start the car one day and it didn't want to start and her let it as is since then.
I've attempted to get it started and manage to do, however a lot of white smoke with strong raw diesel smell is coming when accelerating. I have a feeling it could be a faulty injector or the hpfp itself or worst case worn piston rings or score cylinder walls. I've put my vcds on it and it's only showing errors of the inlet manifold flaps.
I've taken the measurement of thr injectors and I feel something is odd with some of them specially no.3.

Could anyone pls guide me.
I've attached the image of the measurement.

Thanka Guys much appreciated

'10Q7TDI_Prestige'

Not sure I'd buy that story on this car, unless the owner has a fleet of other cars, but I digress.

Hard to start and poor running after it does start often relates to a head gasket leak, which most often results in a copious amount of white smoke out the back, depending on size of leak. Turbo failures can also result in white smoke out the back. Be sure to check oil & coolant levels, as well as condition. A Block Test kit to check for exhaust gas making it into the coolant is very inexpensive compared to buying a car with a head gasket issue...just sayin'.

Other common issues, which your measured data supports:
"White smoke coming from the exhaust usually points to one point of failure: the injectors. Usually, white smoke indicates that the diesel fuel is not burning correctly. Unburned diesel fuel will make its way through the exhaust completely unused. Be careful of white smoke as it will irritate your eyes and skin."

You should also measure the HPFP pressure output to see if it falls within normal parameters, as it is a known failure point and the heart of the fuel injection system.

A 2006 TDI that's been sitting unused is potentially a time-bomb for problems, although the emissions system was simpler, IIRC. They definitely don't like not being driven. Make sure you understand the costs involved to get it back up & running again, as it will likely be pretty steep.

Cedo21

Thank you really appreciate the informations.
I've got a compression tester kit today and i already have a coolant leak test kit as well. I'm gonna test it when i go next.

I've been doing some research and it looks like it's mostly injectors and common issue.
However i've been looking for a full set and it's quite hard to get 2nd hand one and expensice for brand new. At that price i rather buy another engine and swap it.
Also for some reason this engine was only made btw 2006-2009 and i can't seem to find interchangeable parts for it which makes it even harder.

Would anyone know if the CASA Engine Injectors will work on the BUG engine by any chance?

Thanks and again appreciate the help.

'10Q7TDI_Prestige'

Generally you can use the VW Touareg TDI parts catalog for same engine model, and they will be cheaper to source as well. Most likely, your market switched over the full-on, emissions-centric, 'clean-diesel' engine with the EGR Cooler system, Catalyst, DPF, and Adblue exhaust (Urea) injection systems for the 2010 model year, but don't quote me on that. My general understanding is the 2006 model year added minimal emissions controls, whereas the prior model years are the non-emissions TDI engines. Again, that may be different in your market, but is easily verified by you for the Australian market cars.