Boots control circuit???? maybe?
Thread Starter
Senior Member
Posts like a 4 Banger
Joined: Sep 2007
Posts: 112
Likes: 0
From: waukesha, WI

just had my car scanned and there was a code 0057 (boost control circuit) in the history...i am having a issue now where the boost will only work if i have my MAF unplugged. if it is plugged in when using boost it will only go up to 2-3psi and it just dumps the boost....any ideas?
i have worked on this be for and replaced my BCS witch made it work. then i was haveing all these issues with me getting a code 35 (MAF) ...if you may already know....i replaced about everything...MAF, ECM, O2, even check voltage and cleaned grounds. well now my MAF issue is fixed...but now no boost what the heck is up with that.do i have to trade one for the other...lol
i have worked on this be for and replaced my BCS witch made it work. then i was haveing all these issues with me getting a code 35 (MAF) ...if you may already know....i replaced about everything...MAF, ECM, O2, even check voltage and cleaned grounds. well now my MAF issue is fixed...but now no boost what the heck is up with that.do i have to trade one for the other...lol
Thread Starter
Senior Member
Posts like a 4 Banger
Joined: Sep 2007
Posts: 112
Likes: 0
From: waukesha, WI

i have seen that be for and in this case it is of no use to me at this time...plus it is under construction...lol i think my issue is a little specialized. i dont understand how the MAF is connect to the boost of my supercharger. why would it work one way and not the other...when i first got the car it all worked fine and now i does not...so it is possable
Thread Starter
Senior Member
Posts like a 4 Banger
Joined: Sep 2007
Posts: 112
Likes: 0
From: waukesha, WI

just to straiten something out... the only way i could be getting low boost or the boost being dumped is if there was a vacuum leak, or a bad BCA or BCS? nothing else??????!!!!!!!! right?
Senior Member
Certified GM nut
Joined: Oct 2006
Posts: 2,028
Likes: 1
From: burb of detroit. 2 miles north of 8 mile Rd.

Originally Posted by Triple X
just to straiten something out... the only way i could be getting low boost or the boost being dumped is if there was a vacuum leak, or a bad BCA or BCS? nothing else??????!!!!!!!! right?
Senior Member
True Car Nut
Joined: Aug 2004
Posts: 3,067
Likes: 1
From: In your garage, swipin' da lug nutz

Whoa fellas. Looks like we got some miscommunications here.
MAF = Mass Air Flow sensor. You NEVER want to unplug this...only time this is allowable is at idle to see if the sensor actually is working. If it isn't working, the PCM will default to the values stored inside of it...AND switch to a low-octane table.
MAP = Manifold Absolute Pressure sensor. In SSEi trims, this sensor measures boost and vaccuum, and their sole purpose is to report those numbers to the instrument cluster (unless its a 1996 on up...in that case, there are two sensors...one for the cluster, and one for the PCM).
MAPS go bad, but for the gage operation they could be considered a lifetime sensor. MAPS can also lose their boost/vac signal rubber line. So check ALL your lines, as that particular line ALSO ties into the fuel pressure signal.
MAF = Mass Air Flow sensor. You NEVER want to unplug this...only time this is allowable is at idle to see if the sensor actually is working. If it isn't working, the PCM will default to the values stored inside of it...AND switch to a low-octane table.
MAP = Manifold Absolute Pressure sensor. In SSEi trims, this sensor measures boost and vaccuum, and their sole purpose is to report those numbers to the instrument cluster (unless its a 1996 on up...in that case, there are two sensors...one for the cluster, and one for the PCM).
MAPS go bad, but for the gage operation they could be considered a lifetime sensor. MAPS can also lose their boost/vac signal rubber line. So check ALL your lines, as that particular line ALSO ties into the fuel pressure signal.
Senior Member
Certified GM nut
Joined: Oct 2006
Posts: 2,028
Likes: 1
From: burb of detroit. 2 miles north of 8 mile Rd.

Originally Posted by Triple X
so why would it still work then?
Manifold Absolute Pressure sensor?
the maf is on the throttle body, and the MAP, which controls the boost signal is on the rear valve cover, more toward the drivers side.
Thread Starter
Senior Member
Posts like a 4 Banger
Joined: Sep 2007
Posts: 112
Likes: 0
From: waukesha, WI

the MAF is what i had unplugged...since i was having so many problems with it...now that its fixed...and plugged in...i do not get full boost if any. but when its unplugged i get full boost


