This is a rather long story about how a new -B- car owner almost shelled out 16K in unwanted repairs.... Hopefully this will help someone.

My brother had a mid life crisis and decided to trade in his Merc and buy a 09 CGT. I'm the handy one in the family, so before he wrote the check, he wanted my commitment that I could "handle" a Bentley. I've worked on P-Cars, Bimmers, Mercs and even a Lexus Truck... but never a VW/AUDI group car. I was like... how hard could it be?

We buy the car... it drove like a dream. Boy, the W12 is badass....

A day after taking delivery he starts noticing TPMS module error... I told him to ignore it as these cars are known for their TPMS gremlins....

I meet him again after a couple of days and the car is throwing all kinds of electrical warnings.... TPMS Module Error, KESSY Module Error, SYSTEM FAULT VISIT WORKSHOP messages, the climate control and navigation screen was constantly restarting. The car was beeping every 10 seconds and was almost undriveable....

So, we decided to take it back to the used car dealer the next day to have his mechanic take a look at it... They pulled the car into one of their bays so their "expert" can take a look at it. He calls me about 30 minutes later and said this is beyond his expertise and I need to drive it to another shop.... Just as we were talking, I noticed that he had the car running and the CEL was flashing..... I could also see a plume of smoke from the rear.... I had a heart attack.....

I decided not to drive the car..... called a flatbed and towed the car back home. I started the car to pull it into the garage... and boy, the car was like a fumigator on fire.... smoke everywhere and I could hardly breathe. Full panic set in, I'm thinking its a blown gasket, blown turbo, etc.... I use a standard OBD Cable and ScanXL software and it read stored codes for misfire in cylinders 1-6, MAF failure on bank 1, etc.

We were checking out options and my brother found a local "specialist" in town and decided to have them take a look at the car.

Meanwhile, I came across a youtube video of Jason Giannetti (a.k.a. Bentley Tech NY on this forum) @giannettiperformance rebuilding a W12 motor. I sent an email to Jason and explained the symptoms. He replied back promptly and said the 09 models were pretty solid. He doesn't expect it to be a total loss. He thought it was related to a bad wiring harness at the ECU... I was cautiously optimistic.... Meanwhile I order VCDS and VAS and the waiting game began for the cables and software to arrive.

Two days later, the local "specialist" called and said they diagnosed the problem... he said it was a blown turbo and will cost 16K to fix. All hopes were lost... my brother was willing to hand over the credit card (and a tube of Vaseline).... just so he could get the car running again. I convinced him to flatbed the car back home so I could spend some more time with it...

Brought it back home and noticed the smoke was coming from the passenger side exhaust only. I sent another email to Jason and he called me back. He asked me to check for oil in the lower inter-cooler hoses to confirm that it is in fact a blown turbo. He also wanted me to check the area around the ECU for water and loose wiring harnesses.

I dropped both the lower and upper intercooler hoses on both banks and saw small traces of oil.... nothing significant to cause massive amounts of smoking... I was like WTF..... Blown turbo my ***.

Meanwhile, I use VCDS and there was not a single module without an error. And all the errors were due to low voltage. That was my Ah-ha moment.

I then proceeded to disconnect the negative lead from the main battery and started charging it. It was down to 3V.... and it charged and charged and charged for 48 hours. I also found a ton of leaves behind the firewall near the ECU's and below the wipers.. (Awesome Engineering VW, Keep it up.... )

Once the charger was done with its business, I wire her back and fire her up. And... BOOM we have ignition and no smoke....

I let the car idle for a few minutes and take it for a test drive... I noticed smoke.... I was like WTF... not again.... Decided to drive back home and was stuck in traffic.... noticed that the volume of smoke had reduced and it had a burnt oil smell (not of gasoline/petrol like before)... By the time I reached home, the smoke was gone....

The cars been driving great for the past week... no errors, no gremlins... I'm getting ready to perform the 40K service this weekend.

Long story short, This is what I think happened.....

- The car sat in the used car lot without much running time.
- The used car dealer probably boost charged her just before we took delivery.
- The proper way to charge the main battery (if voltage goes below 12V) is to disconnect the negative lead as the lights in the trunk and other electronics will draw more power than what the charger is supplying.
- When the battery charge was significantly low, it caused the various modules to act erratic including one of the ECUs (The car has two), which probably mistimed the ignition and dumped a load of oil and fuel onto the exhaust / cats (YIKES!).... that triggered the flashing CEL and misfires on Bank 1.
-When the charge was fully restored, the oil in the CATS needed time to burn off....

Many thanks to Jason @giannettiperformance for all his advice and support. He not only saved us a boatload of $$$$$ but also saved the entire experience of buying a Bentley. If any of you have problems you need to get a second opinion on, reach out to him.... Jason is truly a silver lining in a business that's known for incompetence and dishonesty.

I still have one error.... my instruments module is causing the CANBUS to operate in single wire mode. I and reading that this is a problem in VW / AUDI cars... most likely a bad wiring harness or connection that's causing it. It doesn't seem to drain the battery though. Have any of you come across this issue?

 

nice, first thing I did was disable my tpms system in my car. more pain that its worth,

 

Glad you were able to figure it out yourself and save a ton of money. It's always good to learn on your own for future issues.

Did you bother calling back the shop that said a turbo was blown? Seems pretty shady.

 

Actually, I posted a review on google and they called me and apologized. Said it was a honest mistake. They refunded my diagnostic fee and offered a free oil change.

No way I'm letting any mechanic touch this car. If there's a problem that requires engine out, I'm going to ship it to Jason's shop in NY.

 

illusionist810,
I am happy to hear the problems are solved,
I was a Porsche Technician for many years before I started at the Bentley Dealer in 2005. Bentley cars have always kept my interest going in my career of repairing cars. Reading your post is very rewarding to me.
Thanks,
Jason

 

....a great write up and proof there are a lot of people out there who will tell you anything to get into your wallet...have there been any further issues...JimB