Stage 1 MHD tuned N55; potential boost leak? (logs inside)

[Accrual_World]

Recently tuned with MHD stage 1. Started with 93oct map running 93oct gas, but quickly found that there were a bit too many timing corrections. I then switched over to the 91oct map while still running 93oct gas; this seemed to clear up those timing corrections quite a bit. However, I seem to be running a bit under target boost and load; in general just wanted to see what the community thought..

Data-logs are below; both 91 and 93 maps.

https://datazap.me/u/erisola/mhd-sta...=0&data=3-4-15

https://datazap.me/u/erisola/mhd-sta...=1&data=3-4-14

Since the logs I have installed an ER charge pipe and a new boost solenoid, unfortunately to no avail.. nothing has changed in terms of load and boost in regards to their targets. I think my next move is going to be replacing the diverter valve.

Side note question: I believe if I had a boost leak the WGDC % would be a bit higher (trying to make up for the leak) correct? If true, does the Waste-gate not alter its position with a leak that is located within the diverter-valve as opposed to elsewhere ( For example, say, within the chargepipe or between the intercooler piping) within the system?

**UPDATE**

Boost leak pressure tested again, this time up to 15psi found no leaks.

Took some logs and the same issue persists; not hitting target load (off by 20) and not hitting target boost (off by 3-4psi). I decided to test further so I flashed map 0 and hit all targets with no problems (~8-10psi). I then decided to flash the stage 1+ on 91oct just for the hell of it; guess what? hitting all targets with no issues at all (13-15psi).

Seems there are no mechanical issues or boost leaks anywhere at all, but rather something is up with the stage 1 tune..?

***UPDATE 2***

Contacted MHD about the issue and Justin has been monitoring via logs. Customer service is great btw. I will keep updating as Justin and I speak about the issue going forward in case anyone might benefit from this info.

[TurboTom]

I would suggest purchasing a boost leak tester and pressurizing the system before you go blindly replacing everything in the system. I went your route last time and ended up wasting $400 before I finally bought the tester and found my leak between the TIC and IC. It was goodentite but was still leaking badly.

[Accrual_World]

Originally Posted by TurboTom

I would suggest purchasing a boost leak tester and pressurizing the system before you go blindly replacing everything in the system. I went your route last time and ended up wasting $400 before I finally bought the tester and found my leak between the TIC and IC. It was goodentite but was still leaking badly.

Noted, definitely won't be blindly replacing the whole system; CP was on my list of mods regardless and the boost solenoid had 100k on it and was an extremely easy replacement for less than $100, figured, why not?..

Boost leak tester seems like a great tool to have though, seriously considering making one. However, I am really trying to determine how patterns in the log could indicate what type of leak exists. For example, the relationship between wastegate duty cycle % and potential leak locations, if one even exists.

How did you determine you had a boost leak to begin with?

[TurboTom]

Originally Posted by Accrual_World

Noted, definitely won't be blindly replacing the whole system; CP was on my list of mods regardless and the boost solenoid had 100k on it and was an extremely easy replacement for less than $100, figured, why not?..

Boost leak tester seems like a great tool to have though, seriously considering making one. However, I am really trying to determine how patterns in the log could indicate what type of leak exists. For example, the relationship between wastegate duty cycle % and potential leak locations, if one even exists.

How did you determine you had a boost leak to begin with?

I'm not certain but I don't believe there is. I would think if there's a leak (anywhere) in the system, it wont build pressure beyond a certain point and cause compensation with dutycycle.

My car had an obvious leak but wasn't consistent. My dutycycle was very high though. Reaching 80s every pull. Ended up being the TIC leak compounded by an out of adjustment wastegate.

If you're still on the OEM CP, inspect it thoroughly for a hairline crack. Could also be a torn o-ring at 100k.

[Accrual_World]

Originally Posted by TurboTom

I'm not certain but I don't believe there is. I would think if there's a leak (anywhere) in the system, it wont build pressure beyond a certain point and cause compensation with dutycycle.

My car had an obvious leak but wasn't consistent. My dutycycle was very high though. Reaching 80s every pull. Ended up being the TIC leak compounded by an out of adjustment wastegate.

If you're still on the OEM CP, inspect it thoroughly for a hairline crack. Could also be a torn o-ring at 100k.

See that is why i am slightly baffled by not hitting targets, I imagined the duty cycle being much higher if a leak was present. Maybe that 7-10% increase in duty cycle while boost pressure tapers equates to leaking very slowly when the system is pressurized beyond 10psi.

Got the ER charge pipe on there now, no cracks in the original and the o-ring was just fine. However, the original charge pipe was leaking a small amount of oil down the underside at the throttle connection. My assumption was that when the system built pressure it was forcing oil out with a small amount of pressurized air as well.

Do you recall the boost pressure you were off target by with your leak? Most i have seen in my logs is just shy of 4psi and not too frequently, seems to be a pretty steady 2-3psi usually.

[TurboTom]

Here are my logs...

At the start:Here

After fixing TIC leak (Still had wastegate out of adjustment): Here

I'll get a new log now that the wastegate has been adjusted when it stops raining in FL long enough to safely make the run. Also worth mentioning, I had to let off the throttle a bit momentarily on the second log due to something in the road. You can see that reflected in the WGDC as well as throttle position and pedal position.

[Ross4ze]

Originally Posted by TurboTom

Here are my logs...

At the start:Here

After fixing TIC leak (Still had wastegate out of adjustment): Here

I'll get a new log now that the wastegate has been adjusted when it stops raining in FL long enough to safely make the run. Also worth mentioning, I had to let off the throttle a bit momentarily on the second log due to something in the road. You can see that reflected in the WGDC as well as throttle position and pedal position.

+1

[Accrual_World]

Originally Posted by TurboTom

Here are my logs...

At the start:Here

After fixing TIC leak (Still had wastegate out of adjustment): Here

I'll get a new log now that the wastegate has been adjusted when it stops raining in FL long enough to safely make the run. Also worth mentioning, I had to let off the throttle a bit momentarily on the second log due to something in the road. You can see that reflected in the WGDC as well as throttle position and pedal position.

Awesome. Thanks for sharing, this is great to compare to.

This puts things into perspective for me quite bit. Maybe the 2-3psi i am under target just results in a very minor WGDC % adjustment of say ~6-10%. Suppose the curve should be a bit flatter..

The gradual increase in your WGDC % didn't change much between the two logs despite a leak being fixed, imagined it would. Curious to see the log after you adjust the wastegate, def post when you can. Thanks again.

When you used the pressure tester did you attach at the turbo inlet or just between the intercooler and the throttle?

[TurboTom]

Ask and you shall receive... Kinda... Here's the log from today

Looks to me like I still have some type of issue. The car is noticeably better from the last log but I'm thinking there's still room for improvement. I think this weekend I'm going to pull off the intake manifold and verify the seal there is good and that the CP o-ring is still intact. Bummer.

I attached the pressure tester to the turbo inlet pipe. Didn't have any issues with that location. As a matter of fact, if I had connected it to the hot side of the intercooler I wouldn't have found my leak that time.

[Accrual_World]

Originally Posted by TurboTom

Ask and you shall receive... Kinda... Here's the log from today

Looks to me like I still have some type of issue. The car is noticeably better from the last log but I'm thinking there's still room for improvement. I think this weekend I'm going to pull off the intake manifold and verify the seal there is good and that the CP o-ring is still intact. Bummer.

I attached the pressure tester to the turbo inlet pipe. Didn't have any issues with that location. As a matter of fact, if I had connected it to the hot side of the intercooler I wouldn't have found my leak that time.

Looks like we may be having similar issues here. Boost pressure tested my system last night and found a leak in the IC to CP connection; fixed it and retested boost up to about 12psi. No more leaks were found, however after logging, absolutely nothing has changed.

Logs look similar to yours, however, lower WGDC % and different target/actual boost amounts. Baffled at what it could be at this point. Going to pressure test again tonight up to 15 psi and see what that reveals. Might end up just replacing the diverter valve for the hell of it, just to see if that will do anything.

[Alturiak]

Did you guys ever figure out what was causing your high WGDC? I'm trying to figure mine out as well, so I'm curious what your solution ended up being.