2009 Touareg Starts and Dies

[Ystersaag85]

Hello,

My 2009 V6 TDI (CASA Motor) has a starting problem I can't get on top of. VCDS shows no error DTC's. I took a trip to Polokwane and back (Centurion), the car ran perfectly fine. Stopped for coffee and nature call a few times and had no issues. Got home, next morning she won't start. It does crank though. Being out of ideas, I walked around and unplugged the MAP sensor (not MAF), turned the key and she fired right up but in limp mode. I bought a new MAP sensor from VW, replaced the old one but problem still persists so I don't think it's the MAP sensor but unplugging it put the car in limp mode which let it start. Yesterday I kept cranking for a bit longer and it hesitated and started with MAP connected. It's smoked heavily and had a strong diesel smell but would struggle to rev up. I made 3 videos to try and show what's happening:

https://youtu.be/LaIZsS5dzoM (No start all sensors connected)
https://youtube.com/shorts/Kf76RnxFf_0 (Start with MAP unplugged)
https://youtu.be/9X7GL-n9wSA (VCDS with MAP unplugged)

I made contact with Stephan yesterday afternoon but felt bad bugging him over a weekend so I thought I'd make a post to see if anyone else might have had the same issue. Maybe another note, when it started the engine sounded normal, no noises or anything at all that would make me think it's a mechanical issue on the engine. I also couldn't find any blown fuses. Sorry the for the french in one of the videos at the end.

I'd appreciate any thoughts.
Cheers

[mk2-phreak]

Stephan's the best man, rather wait for him to have a look

[missioner]

Stephan's the best man, rather wait for him to have a look

I agree with this statement 1000000%

For the big VW diesels the man is untouchable.

I say make an appointment to drop the car off by him and let him work his magic.

Sent from my 2107113SG using Tapatalk

[Ystersaag85]

Thanks. I've been scouring VCDS up and down but can't figure it out. I forgot the previous owner had a re-map done by "Eagle Tuning". I'm wondering if this is maybe why the problem isn't showing up on VCDS. These cars are fantastic but if you don't understand the logic in the software/electronics you're in for some fun.

[mk2-phreak]

Bad remaps, Stephan is gonna have fun with this one (not the first time a bad remap has caused issues or made diagnostics more difficult than necessary)

[Ystersaag85]

Hi. My car runs like a charm again. I took your advise and waited for Stephan. He had a look at it with diagnostics but nothing odd came up. Then as you say, he had fun. I sat with him in the car and he gunned it for quite a long stretch. I was watching the mirror to see if there are cars behind us and at that instant she blew out black smoke and took off like a boeing again. Since then, no issues at all. He said it had carbon buildup, because "I drive like pissy" . Basically explained to me it needs to be warmed up (poot foot), every now and then to clean it out. I really don't push it at all, I'm a Landy guy also and have a mind set with this car not to drive the **** out of it on order not to break it but he says they can easily handle it. So in summary, there was mechanically nothing wrong with it at all, I actually caused the problem. Thanks for the replies and pointing me to Stephan, it was well worth the wait.

[mk2-phreak]

I've noticed my 3.0 TDi also needs a good run occasionally when it starts to feel lethargic

[Ystersaag85]

I couldn't figure it out. Because there were no DTC's it threw me off completely. My mom has an Audi A1 diesel. It did the same but she says there's a light on the dashboard and when it happens she takes it on the highway for good run then it's back to normal. It's interesting that the Touareg (or just mine), didn't show anything. I took the T out on a 150km run yesterday, kept it in sport mode and held the revs at 3000 most of the way. Like you say, there's a difference afterwards. I'm assuming it's heating things up in the exhaust, turbo etc to clean out the crap. She runs just fine now.