[abren]

Hey all,
I installed an AMS FMIC and lower charge pipe a few days ago and whenever the car gets into significant boost there's a loud rushing air sound almost like a "whooshing" sound, almost like an EWG. Is this normal for the car to sound louder like this after adding a FMIC?

Car is driving fine and building boost just fine - peak boost appears to be normal as well.

Although the car seems to be running strong/hitting peak boost, I suspect this is probably a boost leak but I'd like to hear some other opinions.

Info:
2010 335i
VRSF catless DPs
PE mod
Cobb charge pipe
AMS intercooler and lower charge pipe
BQ tune

Edit - here's my last log - http://datazap.me/u/abren/bq93-ije0s...p?log=0&data=1

[bigdaddyaaron]

Originally Posted by abren

Hey all,
I installed an AMS FMIC and lower charge pipe a few days ago and whenever the car gets into significant boost there's a loud rushing air sound almost like a "whooshing" sound, almost like an EWG. Is this normal for the car to sound louder like this after adding a FMIC?

Car is driving fine and building boost just fine - peak boost appears to be normal as well.

Although the car seems to be running strong/hitting peak boost, I suspect this is probably a boost leak but I'd like to hear some other opinions.

Info:
2010 335i
VRSF catless DPs
PE mod
Cobb charge pipe
AMS intercooler and lower charge pipe
BQ tune

check your connections. sounds like a boost leak for sure. If you took a log, check out your wgdc.

[samuelmccarthy13]

Only way to find out is to log and see if boost is reaching target properly. Both FMIC and Charge Pipe are possible places for boost leak, although if leak was significant you would be given 30FF code

I had a similar sound after not tightening down the (lower chargepipe tube) to (chargepipe) hose connection tight enough after a walnut blast. Car felt "normal", pulled strong, and NEVER threw a code but after a couple pulls, the hose popped off as soon as I closed the throttle.

Limped it home, cranked down on the t-bolt, and all has been well for the last ~3k miles.

[stanlalee]

Originally Posted by bigdaddyaaron

check your connections. sounds like a boost leak for sure. If you took a log, check out your wgdc.

This. If you have a small leak but are still meeting boost your WGDC will go up as the turbos work harder to make boost. You shouldnt hear anything appreciably different.

[AW335OME]

Only time I had experienced a sound like you described was when one of the couplings to my FMIC came loose and I had a noticeable boost leak and drop in power.

[abren]

Thank you for the insight everyone. I haven't had a chance to really take a close look at it due to a hectic work schedule so far this week. The tuner didn't say anything looked wrong in the datalog aside from fuel trims being close to maxing out. A boost leak would probably be quite noticeable in a datalog, no?

If anyone wanted to take a look, here is the most recent log http://datazap.me/u/abren/bq93-ije0s...p?log=0&data=1

[abren]

Just a thought, could it possibly be a bad diverter valve?

[madmantwo]

Originally Posted by abren

Just a thought, could it possibly be a bad diverter valve?

It could be a bunch of things...FMIC, CP/throttle body connection, DV, among others.

I'm not an expert on reading logs, and I've never seen ones using quite the parameters you are logging, but it looks like there's a pretty big difference between requested PSI and absolute PSI. Boost leak?

However, I am also pretty sure you're not running 30PSI, so I have no idea what those parameters actually mean. WGDC seems OK. AFR seems crazy lean during max requested load, isn't that bad?

Someone else should chime in who knows what they're talking about

[Jeff@TopGearSolutions]

Sounds like a boost leak. Tighten up those clamps and make sure they are square on the pipes.

[Sgop335]

Originally Posted by abren

Just a thought, could it possibly be a bad diverter valve?

You are off by 2-3 psi on the boost. BUT

Your fuel trimes are fully Maxed out!

And you are running very lean as hi as 17. Dangerous.

Contact your tuner.

[abren]

Originally Posted by Sgop335

You are off by 2-3 psi on the boost. BUT

Your fuel trimes are fully Maxed out!

And you are running very lean as hi as 17. Dangerous.

Contact your tuner.

That's exactly what he said. It does appear to be a boost leak. He sent me a new map and I'll try to see exactly what's going on over the weekend. Hopefully no damage has been done :/

This is a log I did earlier on the revised map; does it appear safe for the next few days?

http://www.datazap.me/u/abren/log-14...og=0&data=1-20

[madmantwo]

Originally Posted by abren

That's exactly what he said. It does appear to be a boost leak. He sent me a new map and I'll try to see exactly what's going on over the weekend. Hopefully no damage has been done :/

This is a log I did earlier on the revised map; does it appear safe for the next few days?

http://www.datazap.me/u/abren/log-14...og=0&data=1-20

That looks much better, no longer are running lean

[abren]

Originally Posted by madmantwo

That looks much better, no longer are running lean

Does it appear to be knocking, pulling timing, anything else bad? Pardon my ignorance, I'm really unfamiliar with how to read logs.

[madmantwo]

Originally Posted by abren

Does it appear to be knocking, pulling timing, anything else bad? Pardon my ignorance, I'm really unfamiliar with how to read logs.

Nah looks fine to me. Small timing corrections after shifting, that's it. Totally normal

[abren]

Originally Posted by madmantwo

Nah looks fine to me. Small timing corrections after shifting, that's it. Totally normal

Thank you very much! I'm doing the boost leak test on Sunday so hopefully it's just something quick and easy.

[Jeff@TopGearSolutions]

You dont necessarily need a boost leak test, yet. Just try clamping down the intercooler clamps and charge pipe clamps. Takes 5 minutes.

[abren]

Originally Posted by Jeff@TopGearSolutions

You dont necessarily need a boost leak test, yet. Just try clamping down the intercooler clamps and charge pipe clamps. Takes 5 minutes.

Update - you guys were right. Boost leak on the hot side. The seal was tight on one side so when the car would build boost, the unsealed part of the coupler would open up making that wooshing noise. All better now