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Forced Induction All questions and problems regarding Superchargers, Turbos, NOS, ZEX, intercoolers, water injection, etc.

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Old 08-31-2004, 01:39 PM   #21
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Quote:
Originally Posted by willwren
That sounds familiar. That should be the first thing checked. Did you ever do it?
How about you do some work
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Old 08-31-2004, 01:41 PM   #22
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I gotta take a break every now and then.

I told this crazy canuck to check that early in the post, but I didn't see where he did it or not.
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Old 08-31-2004, 02:09 PM   #23
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Yes Doc J.. it spiked and reacts to quick burps of gas ( 1.XX Volts.. it was quick ).. didn't try to gradually increase throttle since it'* in park and free revving so didn't want to rev hi for long without load and sure as hell not going to stick my head, body in there and let someone power brake

Checked the movement of the BCA and it seems to move freely when off with a spring feel of restraint.. and power brake and see it moving up into the BCA when the more gas is applied..

Around town.. It has no problem it seems below zero.. but for example if I need to pass and I romp on it some but not to WOT.. the gauge will fly up to boost.. but it will drop down in 2 steps.. roughly bout 1.5 seconds apart.. and you can see the needle wiggle as if tryin to climb back up but won't.. and it would drop it back down to slightly above zero... and I can that initial oomph feel but as the boost drops.. I can feel it

But there will be times it will drop down to the first mark of boost before zero.. and @ times it'* higher.. I was wondering if maybe the vacuum line to the MAP maybe clogged somehow.. will have to get my hands on some compressed air and see.. doubt thats it.. but worth a shot.

Read for codes again.. and still none stored.
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Old 09-07-2004, 10:37 AM   #24
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OK BCA movement and the lil "L" move fine and checked vacuum line, they hold vacuum ( ala vacuum gauge ). Wondering if it could be the spring the Actuator (Bruce recommendation ). So wonderin if anyone with series II L67 with access to a vacuum gauge can do me a favor and find out how much vacuum pressure is required before the actuator fully opens and dump the boost on the actuator.

thanx
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Old 09-21-2004, 11:29 PM   #25
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Well, since we are on the subject. I have noticed a dust line on my BCS. The line was about an inch from the bottom though. How could I disconnect this BCS, or atleast let me have full boost?
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Old 09-22-2004, 01:47 AM   #26
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Quote:
Originally Posted by Drifter420
OK BCA movement and the lil "L" move fine and checked vacuum line, they hold vacuum ( ala vacuum gauge ). Wondering if it could be the spring the Actuator (Bruce recommendation ). So wonderin if anyone with series II L67 with access to a vacuum gauge can do me a favor and find out how much vacuum pressure is required before the actuator fully opens and dump the boost on the actuator.

thanx
Holy crap, I lose track of threads that don't email me when updated. Sorry this was like a month ago. Is it still an issue? Its interesting you say it goes to boost then backs off. Makes me think either a leak or the pcm is pulling boost for some reason..What have you figured out since last?
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Old 09-22-2004, 10:18 AM   #27
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Well.. thinkin it was BCA springs that maybe weak.. checked the MAP sensor.. and they both read low.. Bruce was nice enough to read his MAP sensors on his 97 also for me, and mine was way off He got 4.8V and 2V @ idle. While I have [email protected] idle and 1.8V. ON Both..
So I think the PCM is on it'* last leg... if that'* the case.. INTENSE PCM??

But was also thinking.. how would the MAP or PCM dump boost? I was under the assumption that they control via BCS so if that thing is bypassed, there shouldn't be able to dump boost unless there'* a built in bypass somehwere else? ( Like for shifting between gears and such? ). I'm not Boost headed in knowledge.. so wat you think? Everything so far points to PCM. But can't see how it dumps boost...

Saveing up the coinage for the PCM
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Old 09-22-2004, 12:34 PM   #28
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Quote:
Originally Posted by Drifter420
Well.. thinkin it was BCA springs that maybe weak.. checked the MAP sensor.. and they both read low.. Bruce was nice enough to read his MAP sensors on his 97 also for me, and mine was way off He got 4.8V and 2V @ idle. While I have [email protected] idle and 1.8V. ON Both..
So I think the PCM is on it'* last leg... if that'* the case.. INTENSE PCM??

But was also thinking.. how would the MAP or PCM dump boost? I was under the assumption that they control via BCS so if that thing is bypassed, there shouldn't be able to dump boost unless there'* a built in bypass somehwere else? ( Like for shifting between gears and such? ). I'm not Boost headed in knowledge.. so wat you think? Everything so far points to PCM. But can't see how it dumps boost...

Saveing up the coinage for the PCM
mmm...I wouldn't go buying a PCM just yet. Did you check the voltage feed to the MAP sensors? They should be getting 5v.

You're right, I didn't remember you had the bcs bypass done. Unless I'm not thinking clearly it should have effectively taken the PCM out of the picture. There isn't a lot of options to look at to diagnose this...Vacuum leaks, BCS, BCA, BCV, MAP, and other load sensors depending on the PCM'* control. Without the PCM having control that should be down to vacuum leaks, BCA and BCV..am I missing something? Since at some point it does go full boost, and on the other end does have -10 I would think we could eliminate the BCV and BCA as they're obviously capable of full movement. That leaves vacuum leaks. I guess it is still possible that the BCA has a leak in it, allowing inital full boost but slowly leaking back down...but didn't you say it works fine at WOT?

I'm starting to wonder if this is totally unrelated to the supercharger and associated actuators. Maybe at that throttle the engine isn't keeping steady vacuum...Coffee will help this
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Old 09-22-2004, 04:31 PM   #29
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This COULD be caused by a leak at the SC outlet gasket. This sucker was immersed in water for awhile, then sat for a long period of time. Is your lower intake manifold oxidized in any way?

Would it be a good idea to pull the SC and simply clean the mating surfaces, install a new outlet gasket (cheap) and see where you sit? It might be worth it. That'* a fiber gasket. We've seen a car recently that had a leak from simply missing a torque sequence.

The environmental impact of the swim and storage may be causing this.
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