Deeds' Q5 TDI Ownership Log

Natefank2

Member
Joined
Dec 7, 2020
Location
CA
TDI
A6 TDi
I have stock air intake other than an AFE Dry Flow filter which allegedly may flow a tiny bit more than OEM. As I am sure you have seen here many in the TDI world feel OEM intake sizes/paths etc. are nearly fully maximized already for the maximum power you could squeeze out of a stock turbo.

If, as in your case, you are installing a larger aftermarket turbo than it fully makes sense upgrading MAF and sometimes a bar map sensor upgrade too.

Diesel,
If we are talking about stock turbo then yes, the stock intake is fine, but with an upgraded turbo, you need to upgrade the intake, it's too restrictive. You will notice a quicker spool and more power throughout with the upgraded intake.

You need to upgrade both MAF and BAR sensor for the upgraded turbo. The BiTDi MAF housing is larger and the sensor inside is better suited for the increase in flow that the upgraded turbo is going to produce. As for the BAR sensor, max psi for the 3 bar sensor is about 45.5, I'm not sure about your turbo but mine is pushing around 48psi, which is more than the 3 bar is rated for.
 

Natefank2

Member
Joined
Dec 7, 2020
Location
CA
TDI
A6 TDi
@Pittdawg I just reread this thread and was wondering why you went through the hassle of having a metering valve installed when you are still on a stage 1 tune? Your stock fuel pump still has plenty to give before adding the metering valve. Myself and @DieselDeeds would need the metering valve if we wanted to push our fuel pumps more. I'm personally maxed out on the fuel pump and a metering valve would help squeeze a few more ponies out.
 

Pittdawg

Veteran Member
Joined
May 28, 2018
Location
Los Angeles
TDI
2014 Audi Q5 TDI
Darkside measured 6 hp and 5 lbs torque gains on just a 2.0 TDI
Darkside measured 13 hp and 50 lbs torque gains on their project 3.0 TDI which had 315 hp before swapping in the metering valve.

My stage 1 tune is for 300 hp; I then added the BITDI intercooler, Magnaflow Catback exhaust and a TCU tune meaning I am right around that 315 hp mark Darkside's project car was at.

The additional torque is obvious.
 

Natefank2

Member
Joined
Dec 7, 2020
Location
CA
TDI
A6 TDi
Yes they did get a pretty good increase in power from the metering valve, but that was after they had already done the turbo upgrade and their CP4 fuel pump was maxed out, it says it in the description of the part.

Your car is 300BHP Darksides car is 300+WHP, there's a huge difference, there's no way to get to 300WHP without deletes.

I'm sure the torque is obvious but you would have gotten the same results, probably cheaper, by just upgrading your tune or trying to get APR to add more fuel to your tune.
 

DieselDeeds

Veteran Member
Joined
Dec 10, 2018
Location
Moved states! : )
TDI
2014 Q5 TDI S-Line + Black Optics Package
I haven’t installed the metering valve yet! I’m working through a few quirks right now- I keep getting an injector balance/fault contribution code for two of my injectors. The code is sporadic and intermittent and when I do throw the code, it has always been around ~1500rpm. I haven’t noticed any power loss but I do get a slight but noticeable rough idle when I put it in reverse. I’ve emailed Malone, Bobby, and Darkside, and apparently it’s not something they see often so they couldn’t offer much advice. If there’s anyone here who has seen this before and has a solution, please post it here :) (Oilhammer- throw your cape on and save the day)!

Until then, I just bought the VW/Audi slide hammer and injector pulling equipment, all of the one-time use/mandatory replacement parts to pull the two injectors (gaskets, seals, bolts, etc.). I’m going to pull them out this upcoming weekend, spray insides with brake cleaner, let them sit in some chem-dip, spray again, reinstall, and cross my fingers.
 

Pittdawg

Veteran Member
Joined
May 28, 2018
Location
Los Angeles
TDI
2014 Audi Q5 TDI
Yes they did get a pretty good increase in power from the metering valve, but that was after they had already done the turbo upgrade and their CP4 fuel pump was maxed out, it says it in the description of the part.

Your car is 300BHP Darksides car is 300+WHP, there's a huge difference, there's no way to get to 300WHP without deletes.

I'm sure the torque is obvious but you would have gotten the same results, probably cheaper, by just upgrading your tune or trying to get APR to add more fuel to your tune.
Deletes don't really add any power unless your DPF is clogged, as confirmed by Darkside in their very same build thread that featured the metering valve.

The APR tune is on par with the stage 2 power levels others offer so remapping alone cannot accomplish the torque gains of physically providing the engine with a higher flow of diesel, which is why the torque gains are so high on the uprated metering valve.

If the metering valve offends you so much, don't get one.
 

Natefank2

Member
Joined
Dec 7, 2020
Location
CA
TDI
A6 TDi
Deletes don't really add any power unless your DPF is clogged, as confirmed by Darkside in their very same build thread that featured the metering valve.

The APR tune is on par with the stage 2 power levels others offer so remapping alone cannot accomplish the torque gains of physically providing the engine with a higher flow of diesel, which is why the torque gains are so high on the uprated metering valve.

If the metering valve offends you so much, don't get one.
I just went through Darkside's build tread again (That is what made me want do do all the work to my car) and I don’t see anywhere where they show a dyno before and after the DPF delete, they show one with dpf delete with and without a tune.

But if they say it makes no power difference then why did they delete the DPF and secondary cat?

I can tell you from experience, working with Malone Tuning and Bobby Signh making their stage 3 tune, that just having the secondary cat still installed creates a ton of back pressure in the exhaust. Back pressure makes a less efficient and hotter turbo which means less power.

Yes, remapping can accomplish the torque gains of installing a metering valve, your fuel pump isn't maxed out. If your fuel pump was maxed out, like mine is, then a metering valve would be beneficial, but on just a stage 1 APR tune your fuel pump isn't even close to being maxed out.

I'm not offended by the metering valve, I'm just confused as to why someone would pay so much to have something installed that isn't necessary and honestly probably provides minimal gain on a pretty stock car.
 

Pittdawg

Veteran Member
Joined
May 28, 2018
Location
Los Angeles
TDI
2014 Audi Q5 TDI
"Our car at this point had the DPF removed and a 3" exhaust, as detailed in our previous Blog. We have discussed many times that when functioning correctly, the DPFs offer little to no restriction and the larger capacity engines (2.7 and bigger) are not as known for blocking up for fun as the smaller engines."

 

DieselDeeds

Veteran Member
Joined
Dec 10, 2018
Location
Moved states! : )
TDI
2014 Q5 TDI S-Line + Black Optics Package
You two^^^ No more bickering. Just help my solve the codes my engine is throwing: injector balance/fault contribution for injectors 2 and 6.
 

Pittdawg

Veteran Member
Joined
May 28, 2018
Location
Los Angeles
TDI
2014 Audi Q5 TDI
Never heard of that fault code being triggered did you try the cleaning process yet? I know they are expensive to replace so I would definitely start there.
 

DieselDeeds

Veteran Member
Joined
Dec 10, 2018
Location
Moved states! : )
TDI
2014 Q5 TDI S-Line + Black Optics Package
I honestly haven’t had anytime to take the injectors out and clean them. It’s been running completely fine though and I haven’t had any further issues and that issue hasn’t worsened. I have all the tools and the replacement parts in my garage so I think my buddy and I might take a stab at it this weekend. I drove it 300mi round trip this last weekend with the fam and a packed trunk; we averaged ~35mpg going around 75 most of the way. I’ll definitely post back here after I do the cleaning process!
 

commedeschatons

Well-known member
Joined
Jan 6, 2019
Location
dtw
TDI
2003 ALH Wagon 5mt, 2016 VW Touareg TDI, 2014 Q5 TDI, 2011 335d Msport, 2009 Q7 TDI
I honestly haven’t had anytime to take the injectors out and clean them. It’s been running completely fine though and I haven’t had any further issues and that issue hasn’t worsened. I have all the tools and the replacement parts in my garage so I think my buddy and I might take a stab at it this weekend. I drove it 300mi round trip this last weekend with the fam and a packed trunk; we averaged ~35mpg going around 75 most of the way. I’ll definitely post back here after I do the cleaning process!

Have you tried running a tankful or two of some injector cleaner (e.g. Hotshots, Amsoil etc) ?
 

DieselDeeds

Veteran Member
Joined
Dec 10, 2018
Location
Moved states! : )
TDI
2014 Q5 TDI S-Line + Black Optics Package
I haven’t used an injector cleaner but I’ve always used Stanadyne diesel additive in the past and then I switched to Optilube XPD the same time I changed out the turbo.. and also added a branch chain resonator shortly after to kill a ton of drone. Sooo I inadvertently tossed in a couple extra variables that could be causing this problem haha. I already have all of the injector pulling equipment and have been reading manuals and watching some YouTube videos on removing injectors so I’m basically a pro technician :cool:. I figure I might as well clean and soak the injectors for some preventative maintenance and hopefully fix the problem.

Order of potential issue resolution:
1. cleaning the injectors
2. I’ll take the branch chain resonator off
3. Switch back to Stanadyne diesel additive

I realize switching the diesel additive should probably be first but I think it’s super unlikely that the additive is causing the problem considering everyone and their diesel-driving grandmas love Optilube XPD.
 

commedeschatons

Well-known member
Joined
Jan 6, 2019
Location
dtw
TDI
2003 ALH Wagon 5mt, 2016 VW Touareg TDI, 2014 Q5 TDI, 2011 335d Msport, 2009 Q7 TDI
Hi what is a "branch chain resonator"? This is on the exhaust?
 

commedeschatons

Well-known member
Joined
Jan 6, 2019
Location
dtw
TDI
2003 ALH Wagon 5mt, 2016 VW Touareg TDI, 2014 Q5 TDI, 2011 335d Msport, 2009 Q7 TDI
Whoops. I meant side branch resonator. I have no idea why I put branch chain. Yes- it’s on the exhaust and killed a ton of drone. I’d post a picture but it seems this website has made it super difficult to attach pics now

Like a helmholtz resonator ? That's really smart ! Did you tune it to kill that annoying ass drone at 2k? These engines are so quiet straight piped but that drone is so annoying at 80mph.
 

DieselDeeds

Veteran Member
Joined
Dec 10, 2018
Location
Moved states! : )
TDI
2014 Q5 TDI S-Line + Black Optics Package
Like a helmholtz resonator ? That's really smart ! Did you tune it to kill that annoying ass drone at 2k? These engines are so quiet straight piped but that drone is so annoying at 80mph.
Exactly that. It helped a ton within the 1700-2100 rpm range. You’re saying our cars are quiet when they’re straight piped?! I had to have done something wrong with my straight pipe then because it’s loud as hell. Maybe I have some unnecessary bends in the pipe or when the single pipe Y’s off to the dual exit or something; I’ve contemplated putting my stock tailpipes back on to quiet things down.
 

DieselDeeds

Veteran Member
Joined
Dec 10, 2018
Location
Moved states! : )
TDI
2014 Q5 TDI S-Line + Black Optics Package
Just to update - My neighbor and I took out all of my injectors, plugged the injector holes with ear plugs that I put down there with some long forceps, cleaned the injector seats really well, decided to buy all 6 new injectors while I was replacing one (just to get ahead of any future maintenance with fuel delivery), installed new injectors, recoded them to the ECU via VAGCOM, primed the lines, started her up and everything runs great! I have pictures that I took with my endoscope of the whole injector seat cleaning process. No more rough idle in reverse, no more check engine lights, everything runs amazingly well.
 

Natefank2

Member
Joined
Dec 7, 2020
Location
CA
TDI
A6 TDi
That's great to hear! Maybe send the injectors out to some one and have em tested to see what was going on?
 
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