Ugh.... No Boost.... AGAIN!!!!!
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From: Halifax, Canada 91SSE / 97SSEi

Ok... the car (97) has been sitting for around 2 weeks while I've been enjoying the 91.
Today I dropped the 91 off at the mechanic and got in the 97.
First thing I noticed was she was sluggish off the line... I looked at my boost... it only goes upto ZERO and then stops. I scanned the car but only found a code for Evap Emissions (see my other thread).
I'm thinking bad BCS again, but it was just replaced less then 4 months ago..... ARG!!!
Is there anyway to test/run the car w/o using the BCS?
Today I dropped the 91 off at the mechanic and got in the 97.
First thing I noticed was she was sluggish off the line... I looked at my boost... it only goes upto ZERO and then stops. I scanned the car but only found a code for Evap Emissions (see my other thread).
I'm thinking bad BCS again, but it was just replaced less then 4 months ago..... ARG!!!
Is there anyway to test/run the car w/o using the BCS?
Without using the BCS? There'* the Bypass trick that some people do. There are stickies here for that.
If you pull the plug out of it you're only going to run ~ 2psi MAX. So check your connections.
If you pull the plug out of it you're only going to run ~ 2psi MAX. So check your connections.
Thread Starter
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From: Halifax, Canada 91SSE / 97SSEi

Originally Posted by BonneMeMN
Without using the BCS? There'* the Bypass trick that some people do. There are stickies here for that.
If you pull the plug out of it you're only going to run ~ 2psi MAX. So check your connections.
If you pull the plug out of it you're only going to run ~ 2psi MAX. So check your connections.
I'm going to wait for the engine to cool, and then take another look around.
The bypass just disallows the PCM from dictating boost. If it'* a sensor or PCM problem, that would get you boost back.
With the Evap and boost both being bad right now, I'd be looking for a vacuum leak somewhere. It'* the common factor.
With the Evap and boost both being bad right now, I'd be looking for a vacuum leak somewhere. It'* the common factor.
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From: Halifax, Canada 91SSE / 97SSEi

Originally Posted by willwren
The bypass just disallows the PCM from dictating boost. If it'* a sensor or PCM problem, that would get you boost back.
With the Evap and boost both being bad right now, I'd be looking for a vacuum leak somewhere. It'* the common factor.
With the Evap and boost both being bad right now, I'd be looking for a vacuum leak somewhere. It'* the common factor.
Where would I start to look for a vacuum leak?
Do a search on "boost bypass" in forced induction AND suggestions. Search for all terms.
The first place I'd check for vacuum leaks is the top of the Supercharger where it all comes from, and the vacuum manifold on the firewall, just to the left of the WS wiper motor as you face the engine. Black box, looks like part of the maxifuse relay center.
Does your climate control work fine?
The first place I'd check for vacuum leaks is the top of the Supercharger where it all comes from, and the vacuum manifold on the firewall, just to the left of the WS wiper motor as you face the engine. Black box, looks like part of the maxifuse relay center.
Does your climate control work fine?
It'd be nice if you had a tiny camera you could put under the hood to see if the BCS is closing the valve all the way..hrm...Maybe put something, like foil, on the stopper nut and let a flap of it stick up so that when the BCS closes the valve it'll crush the piece of foil. That way you can tell if its moving all the way or at what point it stops. You might need something more stable than foil (or use a thick/wrapped piece) to hold up to the wind. Meh, the idea is there.
10psi is quite a bit of vacuum leak! haha. I had one of my hoses disconnected and I still got nearly full boost but I might be a freak. If you're leaking that much you should probably hear it.
10psi is quite a bit of vacuum leak! haha. I had one of my hoses disconnected and I still got nearly full boost but I might be a freak. If you're leaking that much you should probably hear it.


