R32 to TDI conversion boost issue

danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Dallas, TX
TDI
None anymore...
I just posted my build thread and I've had a pretty serious issue. I posted the issue in the conversion section, but I figured that I'd post it here as well:
After resolving two different boost leaks with Mike, we went for some logs before dynoing the swap. What we found was that at about 3600 RPM at WOT, the car loses all boost. With less than 45% throttle, this issue did not seem to occur. We swapped N75s, measured vacuum to actuator during runs, change actuator length, swapped ECUs, and checked tunes. We were unable to resolve the issue. I don’t believe there is a rip in the actuator diaphragm because I tested it with a Mighty Vac when initially installing this turbo. We also tested vacuum between N75 and actuator. The ECU looks to be requesting boost, but vacuum drops between the N75 and actuator. I know it is not a rip in the vacuum line because the turbo is happy to hold 27-28 psi of boost pre 3600 RPM. The next steps are monitoring power to the N75 during runs to see if the issue is an electrical command/problem or if it is a mechanical issue with the actuator/turbo (extremely unlikely). While this is a problem that will majorly limit my peak power and stopped me from dynoing the R-TDI, this doesn’t really present an issue with everyday driving. I desperately want to solve this so that I can get a baseline dyno, but it will have to wait until I have time/resources to start fixing this. I have a deep suspicion that the issue has to do with an intermittent relay 109 code that occasionally shows up when scanning the ECU. If that is the case, this may take some serious work to solve. The issue could likely be a short in the ALH wiring harness as well. I am not sure yet, but I have some good places to start looking. All ideas welcome (thanks Matt [FixUntilBroke] and Mike L. for the ideas thus far).
Ideas?
 

eddie_1

Veteran Member
Joined
Dec 27, 2004
Location
Hannover, Germany formerly Toronto & NY
TDI
Jetta Wagon 2003 TDI tuned to 170HP, A6 Wagon 2008 TDI 2.7L tuned to 340HP
Is this not a basic limp mode issue? Boost deviation. What is the boost limit set to? Maybe you start getting boost creep after 3600rpm and it triggers limp mode, the silent type which does not throw a code. Do you have a boost gauge. Can you log it?
 

jsrmonster

Veteran Member - TDIClub Enthusiast
Joined
Apr 22, 2002
Location
Red Lion, PA
TDI
15 Golf SW DSG, RC3 piped, 99.5 Jetta Rocket PD150 6spd 4motion, 2000 ASV110 RC6 "Silverbullet" 5spd Race Car, 2003.5 Cummins QCLB 4x4 "Blue Monster" Jeep CRD juiced, MB Sprinter van juiced up
Unplug the n75 and key on and verify you have n75 fault code. If it gives n18 fault, you got connectors or actuators/hoses swapped. Is car warming up, it could also be correction for cold and warm up mapping, bad CTS, Fuel temp sensor, etc. Baro mapping or sensor could be wonky too. Check boost and baro correlation in field 010.
Send me log of 001, 008, and 011 and it may be obvious. I can think of missing 2D torque limiter, single byte oem limiters, and several other obvious mapping problems.
Jeff

edit: If the logs show the fuel is being pulled, than it may be some anomaly with your 4 motion controller not reporting properly, can you talk to your abs and haldex controller with vagcom? Did you install 50/50 fixed controller and canH/L +K lines working between ecu-haldex-and-ABS? http://www.namotorsports.net/Haldex/Transmission/Haldex/Part-Number=HA.HALDEX.02
 
Last edited:

danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Dallas, TX
TDI
None anymore...
All of these are great ideas. Thanks Jeff for diving so deep into it. Hopefully I can get some logs taken today. I'll post them as soon as I get them.
 

TDIJetta99

Top Post Dawg
Joined
May 17, 2005
Location
Port Jervis, New York, USA
TDI
03... Faster than yours =]
intake hose collapsing?

^^^^^^ THIS^^^^^^

Make sure that none of your hoses pre-turbo are collapsing.. I had one drive me up the wall and it was a 3" silicone hose that was about 8" long that collapsed only full throttle above about 3000rpm..

Look at your MAF readings when it does it.. The car I was working on, it would drop to under 300 when it would fall on its face.. If the MAF was unplugged, it would belch a GIANT cloud of black smoke when it did it too..
 

danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Dallas, TX
TDI
None anymore...
^^^^^^ THIS^^^^^^

Make sure that none of your hoses pre-turbo are collapsing.. I had one drive me up the wall and it was a 3" silicone hose that was about 8" long that collapsed only full throttle above about 3000rpm..

Look at your MAF readings when it does it.. The car I was working on, it would drop to under 300 when it would fall on its face.. If the MAF was unplugged, it would belch a GIANT cloud of black smoke when it did it too..
Well, it's funny that you mention this, because take a look at my turbo inlet piping:


It's a very long section of 3" silicone. I think you may have found it. Now I have to go rig up something else so that I can test, and see if the issue continues.

These of all been amazing suggestions BTW.


Sent from my iPhone using Tapatalk
 

mrchill

TDIClub Enthusiast, Super Secret Diesel Ninja Vend
Joined
Sep 16, 2003
Location
MASS! home of THE WORLD SERIES CHAMPION RED SOX! x
TDI
96 B4v red \ 98 Mk3 green\98 Mk3 Jetta black\ 99 Mk4 Jetta green x2\ 99 Mk4 Golf silver x2\ 99 Mk4 Jetta black\ 97 B4 sedan green\04 JSW gold\03 JSW silver
Common issue....seen it lots. Never have long flex tube. ESPECIALLY silicone.
 

danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Dallas, TX
TDI
None anymore...
Well, I'm going to give this a shot ASAP. I'll then move on to other mentioned solutions if it doesn't work.


Sent from my iPhone using Tapatalk
 

vwmikel

Vendor , w/Business number
Joined
May 5, 2005
Location
Las Vegas, NV
TDI
'94 Golf Sport TDI
The collapsing inlet tube just didn't even cross my mind at the time as I've never seen it happen before. But, thinking about it now, that's definitely where my money is. Apparently there is more inlet vacuum there than I would have expected.
 

TDIJetta99

Top Post Dawg
Joined
May 17, 2005
Location
Port Jervis, New York, USA
TDI
03... Faster than yours =]
Ya, take a piece of hard pipe about 6 inches long and cut it into the middle section of the long silicone hose.. that'll make the silicone sections short enough to stay solid..
 

Whitbread

Vendor , w/Business number
Joined
Jan 21, 2007
Location
Johannesburg, MI
TDI
Several
Take a piece of 3/32" stainless tig rod and wind it around a 3" pipe, put it inside the silicone. That'll keep it from collapsing. Weird that you didn't have the issue with the 2260v :confused:
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
The one thing that does not fit in this solution (the collapsing inlet pipe) is the vacuum going away between the N75 and the actuator...

I hope the inlet tube fixes it, but the above piece does not fit this puzzle...
 

TDIJetta99

Top Post Dawg
Joined
May 17, 2005
Location
Port Jervis, New York, USA
TDI
03... Faster than yours =]
well, it'll take 10 minutes to strengthen that hose so that's a good first step.. Or, stick a cheap cone filter right on the turbo inlet and go for a drive.. That will eliminate all of the pre-turbo pipework..
 

danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Dallas, TX
TDI
None anymore...
intake hose collapsing?
TDIJetta99 said:
Make sure that none of your hoses pre-turbo are collapsing.. I had one drive me up the wall and it was a 3" silicone hose that was about 8" long that collapsed only full throttle above about 3000rpm..

Look at your MAF readings when it does it.. The car I was working on, it would drop to under 300 when it would fall on its face.. If the MAF was unplugged, it would belch a GIANT cloud of black smoke when it did it too..
mrchill said:
Common issue....seen it lots. Never have long flex tube. ESPECIALLY silicone.
You guys were all on the money. Rub87, impressive, it was your first thought before any other responses! I stopped by 034 Motorsports (pretty close in Fremont, CA) and picked up some 3" aluminum tube. Got home and put this together last night:



Tested it tonight in three different runs getting on to the freeway. Car boosted perfectly past 4000 RPM. I'm planing on meeting up with vwmikel in Vegas next week to get some time on the AWD dyno. Thanks for all of the great suggestions everyone!
 

storx

Veteran Member
Joined
Jan 16, 2006
Location
Earth!!
TDI
2009 Jetta CR140, 2010 Corvette Z06
glad you figured this out.. makes me wonder about my setup now. I have all silicone intake on my GTB turbo...
 

fouckhest

Veteran Member
Joined
Aug 26, 2007
Location
g'vegs, sc
TDI
.:GTD, .:R32, DangerRanger
happy to hear this was so simple! looking forward to seeing this thing on an AWD dyno!!:D

glad you figured this out.. makes me wonder about my setup now. I have all silicone intake on my GTB turbo...

this is exactly why there are only 2 pieces of silicone on my entire turbo setup...no questions about failure!
 

danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Dallas, TX
TDI
None anymore...
Thanks. I wouldn't use a complete silicone intake, but I do think it is important to have some silicone. The system does need to have some flex in it.


Sent from my iPhone using Tapatalk
 
Top