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Old 02-02-2006, 03:50 PM   #1
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Well, I talked about the rattling etc...and it turned out to be the harmonic balancer. Ok, so not so bad.

Now for the boost. I said it was sticking around 4-5lbs on the guage. Not so good. They said they tried replacing the boost control solenoid and it didn't help. Their final diagnostic was they had to replace the supercharger because it was "tired and old" - $700. I said no obviously.

I guess I will take this problem into my own hands, since you guys say the */C almost NEVER has to be replaced. And it isn't seized up or anything, it still climbs up to 5lbs nice and quick....just won't go any higher.

So help me please!!! I need booooooost!!
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Old 02-02-2006, 03:52 PM   #2
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Loss of rotor coating? Funky MAP sensor? Vacuum leak between vacuum tree and MAP sensor?
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Old 02-02-2006, 05:02 PM   #3
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Quote:
Originally Posted by J Wikoff
Loss of rotor coating? Funky MAP sensor? Vacuum leak between vacuum tree and MAP sensor?
Hmm...I have no SES code, not sure about vac leaks. The guage does move a bit at idle. Is it possible that the guage is just faulty? Should get it back this afternoon.
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Old 02-02-2006, 05:09 PM   #4
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The gauge is displaying what it'* being told.

The MAP sensor senses manifold pressure and converts it to an electrical signal for the gauge. The sensor itself may be bad, or you may have a vac leak making the gauge not read correctly (Actually a boost leak in this case).

A SC cannot possibly 'lose' 3 psi.
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Old 02-02-2006, 05:56 PM   #5
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im certainly no */C specialist, but i would see if you can get your hands on a scantool. maybe you are getting some KR and the BCS is dumping boost
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Old 02-02-2006, 07:59 PM   #6
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Well, I went back to get the car. Went to drive her home and it made that same horrible squeal (however the rattle was corrected). I was pretty pissed off. I went back, and got the mechanic to go for a drive with me. He heard it and had no idea. The mechanic and I went back and put her on a hoist and he got the head mechanic to look at it. We then power braked the bonne with the hood open, and I think I have a new definition of broken mount.

Under load, the engine rocked back so much a pulley was hitting the torque axis mount and making that god awful sound. The reason it was intermittant? Because it'* winter here, and quite often 100% traction doesn't occur, thus the engine didn't rock back as much. But as soon as I hit dry pavement, and it gets traction, the engine rocks back so hard it does that. Why didn't the mechanics catch it? Because it was snowing this morning.

As for the low boost, he said he repaired some vaccuum lines. They didn't actually put in a new boost control solenoid, he just said it "checked out" as operating fine. (On a scan tool maybe?) Hell, maybe the pulling rubbing up against the torque axis is causing the loss of boost. I can only hope.

Anyway, it should get fixed tomorrow. This better be the end of this.
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Old 02-02-2006, 08:08 PM   #7
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WOW, I never would have thought of that as a squeel problem. Glad that was solved.
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Old 02-02-2006, 09:39 PM   #8
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When the pulley hits the mount, it cold cause the belt to slip and slow the SC down, reducing boost.
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Old 02-02-2006, 10:55 PM   #9
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Quote:
Originally Posted by J Wikoff
When the pulley hits the mount, it cold cause the belt to slip and slow the SC down, reducing boost.
Exactly what I was thinking. I hope so...
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Old 02-03-2006, 06:02 PM   #10
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Ok, all other problems solved except the low boost. Now, to go over what has been mentioned...

Vaccuum lines - mechanic said he repaired any leaks he found.
MAP Sensor - Causes a bad reading in the gauge, but would this not set off a code?
BCS - He said it "checked out" fine on the reading, however does anyone think replacing it would make a difference even if the old one is supposed to be ok?
Loss of rotor coating - Well, I guess I'm just screwed for that one..

Any */C geek help is much appreciated. This isn't too urgent since the car is completely driveable and the roads are messy...but it will be needed soon.
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