P0234 Overboost Condition - Help!

[RedHotVAG]

I have a GTI with the G Revision turbo, JB Stage 1, CTS Catted Downpipe, APR Intake, GFB DV+. I previously ran the Neuspeed Power Module for 6 months with no issues. Now I'm getting the P0234 Overboost Code.

I brought the car to a reputable independent mechanic that specializes in European cars. We have spent 5 hours trouble shooting and still have not found the reason why I am getting this code.

Symptoms:
1) When ambient temperature reaches 26C+, hesitation in 2nd, 3rd, 4th gear pulls, EPC light with P0234 Code

This is what we've done so far:

1) I upgraded to GFB DV+ after getting the code with the stock DV. Didn't help

2) Boost leak test, completed the the PCV Valve in line, no leak. (Next time I go back we will try and bypass PCV valve and do another boost leak check

3) Checked Boost Pressure Sensors and IAT Sensors. Digital readings seem fine, physical check, sensors are clean, no contamination

4) Checked hoses to and from intercooler, seems fine

5) Check boost pressure regulator / wastegate, digital readings are fine, cannot do a physical check as we were told this is now part of the IHI Turbo as one piece

5) Adaptation reset for all sensors - this fixes the problem for half a day, and problem comes back

My mechanic called Neuspeed, APR and VW and they have no idea why people get overboost codes, he messaged George Smooth and we're just waiting to hear back from him. Since I have a Revision G, we do not think it's the turbo itself.

Anyone have any idea what it could be?

 

[gn4rwhals]

JB1 seems to throw this at values above 5psi, I was getting this at 5.25psi but backed it down to 5psi and I haven't had one since.

Alternatively you can take the piston spring out of the DV+ and it will act like a stock DV.

 

[RedHotVAG]

JB1 seems to throw this at values above 5psi, I was getting this at 5.25psi but backed it down to 5psi and I haven't had one since.

Alternatively you can take the piston spring out of the DV+ and it will act like a stock DV.

Do you know what is wrong with the piston spring in the DV+?

 

[gn4rwhals]

Do you know what is wrong with the piston spring in the DV+?

It works too well, its designed to hold boost better but if the car is pulsing the DV to let some out it doesn't open fast enough.

Also what psi are you set at, try 5psi on map 1 and see if it does it.

 

[RedHotVAG]

It works too well, its designed to hold boost better but if the car is pulsing the DV to let some out it doesn't open fast enough.

Also what psi are you set at, try 5psi on map 1 and see if it does it.

gn4rwhals - I'm actually running 4.75 only. Because I don't want to up it until I resolve the issue. Couple questions here for you:

1) My problem only happens when it's warm / hot outside. At 20C / 68F, I have absolutely no issues at all

2) The DV+ came with 1 extra long bolt, I watched the installation videos and that was not used, do you know what that bolt is for?

3) I'm going to try and take the spring out, but could it be a totally different issue entirely?

4) By taking the spring out you mean entirely, as in don't leave any spring in there at all? Or put back the original spring?

Thanks!

 

[gn4rwhals]

gn4rwhals - I'm actually running 4.75 only. Because I don't want to up it until I resolve the issue. Couple questions here for you:

1) My problem only happens when it's warm / hot outside. At 20C / 68F, I have absolutely no issues at all

2) The DV+ came with 1 extra long bolt, I watched the installation videos and that was not used, do you know what that bolt is for?

3) I'm going to try and take the spring out, but could it be a totally different issue entirely?

Thanks!

1) My problem only happens when it's warm / hot outside. At 20C / 68F, I have absolutely no issues at all - Same here, but I have a FMIC so the car stays running well with the lower IATs.

2) The DV+ came with 1 extra long bolt, I watched the installation videos and that was not used, do you know what that bolt is for? - Aftermarket turbo kits with a custom DV housing, that bolt was used in the APR K04 kit on the MK5/MK6.

3) I'm going to try and take the spring out, but could it be a totally different issue entirely? - Possibly, I would giver this a shot, the GFB website states that it can be run without the spring but it will just mirror stock valve function.

 

[RedHotVAG]

1) My problem only happens when it's warm / hot outside. At 20C / 68F, I have absolutely no issues at all - Same here, but I have a FMIC so the car stays running well with the lower IATs.

2) The DV+ came with 1 extra long bolt, I watched the installation videos and that was not used, do you know what that bolt is for? - Aftermarket turbo kits with a custom DV housing, that bolt was used in the APR K04 kit on the MK5/MK6.

3) I'm going to try and take the spring out, but could it be a totally different issue entirely? - Possibly, I would giver this a shot, the GFB website states that it can be run without the spring but it will just mirror stock valve function.

Thanks gn4rwhals, Ok so I removed the spring and the EPC light no longer comes on even in 30 degree weather but I feel like the car is slower for some reason. I did have an EPC light come on prior to putting the spring in. It wasn't officially clears in VAGCOM only the light put out by shutting off the car and back on again. Could that be the reason? I just need to clear it in VAGCOM?

Sent from my SM-N910W8 using Tapatalk

 

[gn4rwhals]

Thanks gn4rwhals, Ok so I removed the spring and the EPC light no longer comes on even in 30 degree weather but I feel like the car is slower for some reason. I did have an EPC light come on prior to putting the spring in. It wasn't officially clears in VAGCOM only the light put out by shutting off the car and back on again. Could that be the reason? I just need to clear it in VAGCOM?

Sent from my SM-N910W8 using Tapatalk

EPC will need to be cleared via VAGCOM or VW Diag Tool, I noticed the same when I had my issues.

 

[RedHotVAG]

EPC will need to be cleared via VAGCOM or VW Diag Tool, I noticed the same when I had my issues.

You're a life saver brother!

Sent from my SM-N910W8 using Tapatalk

 

[Fernflex]

For technical question or troubleshoot you should write George by email.

It is not normal, I have been using jb since January running 5.0, 5.5 and 6.0 e30, 93, 100 and now meth with no issues and my ambients temps never go below 80

 

[gn4rwhals]

For technical question or troubleshoot you should write George by email.

It is not normal, I have been using jb since January running 5.0, 5.5 and 6.0 e30, 93, 100 and now meth with no issues and my ambients temps never go below 80

100% Agree on this, odd that you didn't get the issue, are you DSG?

I think this may be limited to 6MT cars at the moment.

 

[RedHotVAG]

100% Agree on this, odd that you didn't get the issue, are you DSG?

I think this may be limited to 6MT cars at the moment.

Mine is 6MT as well.

 

[Fernflex]

Im dsg!

 

[gn4rwhals]

George said he was re-working the maps for 6MT but also he was going to test the DV+ on one of his cars first.

Something about the torque targets being different for the manuals, honestly not completely sure, I've been just driving my car like a sane person and its doing well.

 

[RedHotVAG]

I beat on my car 24/7. I redline on every commute.

Sent from my SM-N910W8 using Tapatalk