Possible Boost Leak?

[Quirk]

I was driving around today, at wot in 2nd gear, I was at about 4,000 rpms my car hit 15psi and it felt like a hit a brick wall, the rpms wouldn't go further, car started to jerk.

-It won't do this at 10psi, only at 15psi.
-I got a VR-SPEED Short Route FMIC -- Boost leak already? It's brand new.
-Used 1g Crushed BOV.

The FMIC was installed about 2 wks ago, I've been driving it havn't exp this until today. Would a boost leak just come out of nowhere like this, and would it cause the car to jerk at 15 psi when I floor it.

I am going to go to JNZ TUNING tomorrow and see if they can do a boost leak test. But I just wanted to hear some opinions.

Thanks!

 

[virgin_boost]

are you running stock computer or afc. is all of your fuel system stock

 

[cyclonekid77]

Sounds like fuel cut. Are your injectors stock? If so they probably cant keep up with that much boost.

 

[Quirk]

Sounds like fuel cut. Are your injectors stock? If so they probably cant keep up with that much boost.

I am not sure about the injectors. If it can't handle that much boost wouldn't I have exp this when I first hit 15psi? Or would it take time for it to really determine if it can hit that much psi?

 

[cyclonekid77]

With a boost leak, the car will kind of bog because the leak is making the car run rich. When fuel cut happens, the ecu literally cuts off the injectors to prevent engine damage because the car is running too lean. So if your hitting a brick wall, it sounds like fuel cut. Alot comes into play with it too. Temperature, Humidity, ect.

 

[Quirk]

With a boost leak, the car will kind of bog because the leak is making the car run rich. When fuel cut happens, the ecu literally cuts off the injectors to prevent engine damage because the car is running too lean. So if your hitting a brick wall, it sounds like fuel cut. Alot comes into play with it too. Temperature, Humidity, ect.

It's really hard to describe in words, but it wasn't as much as hitting a brick wall. I'd drive 1st gear is fine, 2nd gear, full throttle.... 4,000 rpms the car will jerk at 15psi, car won't backfire, the car stays on so I'd just let off the throttle and shift to 3rd, if I hit 10psi I am ok.

So I am a bit confused why this could be happening.

 

[1sttimedsmr]

There are two possible problems:
-You are experiencing fuel cut due to injectors or maybe fuel pump.
-Your timing might be off.
Do you have logger?

 

[Quirk]

It's not fuel cut, fuel cut would have a pop sound coming out of the exhaust. That isn't happening.

 

[1sttimedsmr]

Can you go pass 4k rpm on 10 lbs boost?

 

[Quirk]

Yes I can.

 

[knochgoon24]

Fuel cut feels like your transmission just fell off the car. You'll swear you broke something when it happens the first time.

It seems like you either:
a. Have a boost leak. You start running so rich that you get no power.
b. Your spark plug gap is too big or they're fouled. Make sure it's still at .028" and use NGK BRE6S or BRE7S plugs. They seem to work best. You're starting to hit the point where people start to go the one step colder (BRE7S).

I had a situation similar to yours where I keep getting the stuttering under higher boost. I was fine at 10psi, but it would buck a 15psi. I pulled my plugs and the gap had opened to .040"-.045" on every one.

 

[AlaskanDsm]

It would help if you could fill in your profile so we can see if you have any other mods. If you are running stock and you are boosting to 15lbs, I also say fuel cut. When I installed new copper crush washers, I forgot to hook up the hose to my wastegate actuator and so after I installed my new cat-back... I boosted to 15 PSI, hit a brick wall, scared the crap outta me, as Knochgoon24 said, I thought I broke something. Never heard a pop or anything like that, the just engine rev down.

check to see if you are running stock injectors and if you are taking it somewhere maybe see if they have any logging stuff.