Q5 3.0 TDI Stage 2 & Deletes -- Smells So Bad -- Strong Odor

sootchucker

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2015 Golf
i hope this helps... on my deleted X5, i had the identical problem. however when i performed the delete on the X5, i removed the cowl and airbox unit in the engine bay. turns out, i had reinstalled it improperly which caused the strong odor in the cabin while standing still. once discovered and reinstalled properly, no issue with smell.
 

PhunkFX

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May 19, 2011
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2014 Audi Q5 TDI S-Line, 2005.5 Jetta TDI (BRM) 6MT (02Q)
i hope this helps... on my deleted X5, i had the identical problem. however when i performed the delete on the X5, i removed the cowl and airbox unit in the engine bay. turns out, i had reinstalled it improperly which caused the strong odor in the cabin while standing still. once discovered and reinstalled properly, no issue with smell.
Thank you. I have also be curious of this, and is an additional concern. We will surely look at this also. Great advice!
 

sootchucker

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no worries. i think the reason i had removed it was to access the ECU, now that i think back.

not sure where it is in the Q5, but if it is in that area and the airbox is not properly sealed, you can have very strong odors entering the cabin even without an exhaust leak.

otherwise, check all openings to the cabin. outside smell is only normal outside obviously and with windows down standing still. (if i am wrong, i stand corrected but as with my scenario in the x5)you should have no toxic smells inside the cabin regardless of AC settings. i tested this thoroughly before and after and i had no smell after i corrected my issue.
 

jscsir10

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oxford ny
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2009 jetta
I was wondering what plugs you unplugged for the egr? I have a regen smell and I think it’s due to the egr still plugged in. I have a stage 2 tune from Malone on my 2015 A6. I will do a full egr delete and a lot more soon, but I can’t find any info on this.
I know with my diesel trucks, once you get the dpf and egr turned off, you need to unplug it all, or it’ll make it smell as if it’s in regen
 

PhunkFX

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2014 Audi Q5 TDI S-Line, 2005.5 Jetta TDI (BRM) 6MT (02Q)
Yeah, that might be the case as well. I have a darkside developments EGR plug that sandwiches in between a pipe on the intake manifold, closer to the block and front of the car.

Though I may just try to get a custom piece made and attach it right to the turbo compressor and block it off there. That is where I see a pipe leaking.
 

trae

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3 prior TDIs - '97 B4 Passat Sedan, '96 Passat B4 Wagon, 2001 NB; Current - 2013 Audi Q7 TDI Pearl White Metallic - 2014 Moto Guzzi California 1400 Touring - 1995 Moto Guzzi 1100 Sport Carb
That will have to be the next step. It shouldn't be coming in the HVAC regardless of how smell it is from the tail pipes, right?

Agreement here - I had a B4 Passat and 1st generation NB TDI back in the day, both running 2x oversized injectors, Stage II and III tuning programs respectively, and 3" straight pipe exhausts with no mufflers......never got any exhaust smell in the cars. There was plenty of soot; it I ran the Passat hard for a few hours, soot that you could write your name in would accumulate on the tailgate.
 

PhunkFX

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2014 Audi Q5 TDI S-Line, 2005.5 Jetta TDI (BRM) 6MT (02Q)
I'm sure it is just a cowl, but I'm working on a solution for the EGR anyhow. I do see the soot. Next time the Q5 is here, I'll try to get some pictures of where I see a small, but high pressure, leak.

Then it will be a matter of removing and re-installing the cowl, as best as possible.
 

DieselDeeds

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Moved states! : )
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Just got back my Q5 back today after DPF/EGR removal. I originally went with the Rawtek w/HF cat. I decided to go catless. The exhaust doesn't stink inside the car at all. There is only a smell if i'm behind the car while it is running or I just turned it off. Although, I notice there is a different sound from when the car is in neutral or park (same sound) versus if the car is in reverse or drive.. there's almost a slight turbo spool sound to it. Did you also notice this sound? If not, i'm wondering if I have an exhaust leak somewhere :confused:
 

sootchucker

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Just got back my Q5 back today after DPF/EGR removal. I originally went with the Rawtek w/HF cat. I decided to go catless. The exhaust doesn't stink inside the car at all. There is only a smell if i'm behind the car while it is running or I just turned it off. Although, I notice there is a different sound from when the car is in neutral or park (same sound) versus if the car is in reverse or drive.. there's almost a slight turbo spool sound to it. Did you also notice this sound? If not, i'm wondering if I have an exhaust leak somewhere :confused:
normal.
 

DieselDeeds

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Of course- glad to contribute (when I can) to the community. The deleted + tune are amazing so far. Gas mileage and power is amazing! So everyone is agreeing it’s normal for there to be a change in exhaust sound between Park/Nuetral and Drive/Reverse? Phunk, I hope you get your car figured out quickly! Cheers.
 

PhunkFX

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Thanks Deeds... I'm working on it.

In the works:
New EGR Pipe (to fix a found leak)
New Tune (an actual known diesel tuner, Malone stage 2 off-road)
New Performance Exhaust (this is for me and for fun)
Check DP for leaks (cover that basis)
Uninstall & Re-Install Cowl (the leak into the cabin might actual be here)
 
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PhunkFX

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2014 Audi Q5 TDI S-Line, 2005.5 Jetta TDI (BRM) 6MT (02Q)
Well, I finally have all of this resolved. It's not easy when I'm just waiting on my brother to do the work, because I refuse to pay a shop when my brother does better work (most of the time).

I have gone though and done a few things that has resolved the smell issue I've been having. Pics to follow.

1) There was a large exhaust leak at the first flange on the Rawtek DP/DPF delete. It was hard to see, but when I finally got my bro to take it all apart, here is what we found:




2) The EGR pipe coming right off the turbo was leaking right after the flange that bolts to the turbo (that's a high pressure leak causing boost surging).

I bought a new pipe and then brought it to a local fab shop and had a custom EGR block off plate made. I already have the Darkside EGR block off installed on the cool side of the EGR cooler.



Now I have it blocked off right at the turbo.





All of the exhaust leaks are sorted, and the EGR cooler has been plugged and is just sitting there doing nothing. I thought about trying to delete it all, but I wasn't about to ask my brother to open that can of worms.

3) The cowl! The cowl/scuttle never really wanted to reinstall and settle correctly. So A few screws were added to seal it,
but you could still see light shining through the cracks when searching. Terrible fix, but honestly, it worked great and was cheap, we just spray foamed lightly from the inside. It worked, I know its not proper, but don't hate too much.

Other changes... for fun I added a magnaflow 3" exhaust. It looks decent and sound decent. A bit meaner and more like a performance exhaust than a straight pipe. I'll get sound videos when it's not raining here in NY.

I've also installed 17.5mm spacers in the front and 25mm in the back. It looks WAY better.





So, my issues are all good now, it runs and drives great. It also doesn't smell anymore. I'm very relieved. The wife is happy and that's what matters.
 

PhunkFX

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Yes. Thank you. The exhaust drones a bit to much for the Mrs. So I'm going to have a Vibrant resonator added in there.

So far so good. Ah Malone tune also. Less aggressive than my other tune, but waaaaay more drivable. They are very similar, but this is much better, IMO.
 

commedeschatons

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thats great to hear. I will check my gasket for the downpipe and youve inspired me to follow your lead on the hot side egr blockoff.
 

commedeschatons

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Oh, and now youre just running the two blockoff plates and have removed the EGR cooler pipe completely?
 

Huskies2710

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Yes. Thank you. The exhaust drones a bit to much for the Mrs. So I'm going to have a Vibrant resonator added in there.

So far so good. Ah Malone tune also. Less aggressive than my other tune, but waaaaay more drivable. They are very similar, but this is much better, IMO.
Very cool and glad you have the smell issue worked out. I hope to do this down the line at some point. The fact that you noted the louder exhaust too lets me know I need to take that into consideratino when Deleting and doing an exhaust upgrade.

Enjoy!
 

PhunkFX

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2014 Audi Q5 TDI S-Line, 2005.5 Jetta TDI (BRM) 6MT (02Q)
You are welcome guys. There aren't too many people out there with mods yet. But more will surely come as they get cheaper...

I might be keen on trying to remove the EGR cooler, but I'm not that brave enough yet.

The EGR pipe is currently cut back from the turbo, and plugged. But yes, hot and cold side block offs are installed.

R
 

Huskies2710

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You are welcome guys. There aren't too many people out there with mods yet. But more will surely come as they get cheaper...

I might be keen on trying to remove the EGR cooler, but I'm not that brave enough yet.

The EGR pipe is currently cut back from the turbo, and plugged. But yes, hot and cold side block offs are installed.

R
The shop that did the tune on my A6 is enticing me to just get the delete. I do not want to run into noxious fumes though. More homework to be done before I commit.
 

PhunkFX

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2014 Audi Q5 TDI S-Line, 2005.5 Jetta TDI (BRM) 6MT (02Q)
The shop that did the tune on my A6 is enticing me to just get the delete. I do not want to run into noxious fumes though. More homework to be done before I commit.
So as long as all pipes are sealed up, as well as the cowl/scuttle is sealed back up correctly, you'll only smell it at a stop with the windows open or when behind the vehicle. Just my 2c. :)
 
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