Problems After Track

[Gregg]

before replacing BCS, do you have an MBC to test in its place? don't forget the vacuum cap required for the plastic intake hose if you hook up an MBC.

if it is the CBV, it's gotta be really really badly torn...if just a small tear usually the car will build boost (like 10psi+), and then start leaking down. Even when my cbv was only being held on by two of the three screws, I still made 6psi with boost pressure leaking heavily out the gap at the lower portion of the cbv connection/surface.

[USMC850T]

Update:

definately not the CBV. Pulled the plate off and the diaphram is perfect. I replaced the vac hose going to it as a precaution.

Now is it more likely that my BCS is tweaked?

When I hit the gas it begins to boost and feels like it wants to go further but cant boost any higher than 5. I cannot hear the wastegate opening like I usually can (very distinct sound coming through the exhaust).

[Gregg]

try disconnecting the hose going from the bcs to the wastegate, taking it out for a drive, and be very careful with how much boost you build. if it goes over 5psi and keeps building when you have your foot down (like gets to 15psi and more) then the bcs is likely the culprit.

could also try bypassing the bcs and hooking up an mbc to see if you make proper boost

[USMC850T]

Gregg you're right on the money, I've got a bad BCS. I took the wastegate vac line off and low and behold it boosts beyond 5. I accidentally pegged my gauge (20psi), but it was at higher RPMs so no biggie.

At this point i understand I can:

A: replace the soleniod

B: Insert an MBC to boost to whatever pressure I desire

C. Use an EBC for some finer boost control

I'm almost tempted to go the EBC route so that I can have my own boost curve and control it relative to RPM so as to aviod bent rods

[Gioseppe]

ebc is waaay better.

you can set the gain on it really slow so it will build the boost slower and let the ecu advance the timing more insted of the ecu seeing 18 all of a sudden and pulling timing.

[prasamin]

Gregg you're right on the money, I've got a bad BCS. I took the wastegate vac line off and low and behold it boosts beyond 5. I accidentally pegged my gauge (20psi), but it was at higher RPMs so no biggie.

At this point i understand I can:

A: replace the soleniod

B: Insert an MBC to boost to whatever pressure I desire

C. Use an EBC for some finer boost control

I'm almost tempted to go the EBC route so that I can have my own boost curve and control it relative to RPM so as to aviod bent rods

EBC

if you want a stock BCS to try, I've got one laying around somewhere, just have to find it. $20 shipped.

[EricF]

Does your CEL come on ever? Just to be sure it works. Because it sure sounds like limp home mode...

If you bypass the BCS and put in a manual controller (why on earth would anyone need an electric controller on the 15G sounds like a $200 solution to a $5 problem), and boost behavior restores itself to what you were seeing before, it is either limp home mode or somehow a bad BCS. BCS does not typically fail, and not typically in that way though so I am cautious on that particular possibility.

I would pull your codes though, seems you have checked most things that would not throw a code. It is getting more and more common on these cars that the CEL bulb has been removed or some similar thing to eliminate questions upon resale.

Actually I would just put in a manual boost controller and leave it like that until you had a substantial problem to deal with :ph34r:

[USMC850T]

Ok I replaced the BCS with one from Prasamin and still the same situation, which would now lead me to believe that it's an electrical problem somewhere between the BCS and ECU. Now after coming home from a week of vacation where my car was only moved in the driveway the CEL is on. I'll figure out the code tomorrow but in the meantime I've ordered a Dawes hybrid MBC. I'm just gonna run like 18 till I go to OCS and then crank it down to like 10 since my mom and bro will drive my car while im gone.