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Old 08-22-2006, 08:30 AM   #11
DINOSAURUS BOOSTUS

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Chuck.. sounds like there are many possible issues.

Ensure you have thoroughly cleaned out the fins of that radiator. Dirt can and does build up.

The heat and possible restriction in your exhaust could very well be what is holding you back.

As for fueling.. you might want to bump up your pressure a little to compensate for some of the mods. However.. I'm in no position to tell you where to put things based on your mods..(or my lack of experience )
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Old 08-22-2006, 08:27 PM   #12
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I'm planning on upgrading to a '95 */C at some point, but I see no reason to do that unless I am getting the desired boost from the current */C. I think I will test the fuel pressue and then pull the exhaust to see what kind of improvement it gives me. Any idea how much pressue I should have at idle and under acceleration?
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Old 08-23-2006, 01:14 AM   #13
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Restricted exhaust will increase indicated boost. Not the problem here.

Fuel pressure will have no effect on indicated or effective boost. Not the problem here.

Low boost is caused by:

1. Belt slippage (real boost loss)
2. Faulty BCA (real boost loss)
3. Faulty BCS (real boost loss)
4. Vacuum leak causing real or indicated boost loss.
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Old 08-23-2006, 07:27 AM   #14
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Where is the BCS and is there a way to test it?
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Old 08-23-2006, 09:42 AM   #15
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The black can is the BCA..the electrical gizmo bolted to the front of it is the BCS.
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Old 08-23-2006, 10:41 AM   #16
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At idle, disconnect the top vacuum line from the actuator (the 1.5" diameter canister). The arm should move full travel. Go for a drive. Do you have full boost? If not, re-connect that line and disconnect the lower line on the driver side and plug it so it doesn't leak vacuum (this is the line from the BCS to the BCA. Do you have full boost?
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Old 08-23-2006, 10:34 PM   #17
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ok, I disconnected the vaccuum line to the top of the BCA and plugged it. I took it for a drive and ran it full throttle. The power seems slightly more sluggish. I then reattched that vaccuum line and disconnected the elbow shaped vaccuum line from the BCA to the BCS. and plugged that vaccuum hose. Still no effect on the gauge and it ran about the same as with the BCA unplugged. I then disconnected the vaccuum hose that runs to the passenger side of the BCS and plugged that. It actually felt like it had slighly more power then, but still no change in the gauge. I don't believe there is any belt slippage. All the belts are new and make no squealing noise. I believe my vaccuum lines are ok. They are new and I don't see any sign of vaccuum loss. Any vaccuum lines you would believe are supect? One more question. My BCS has two connections on the drivers side. The one toward the front is plugged and the one toward the rear is connected by the elbow to the BCA. Is that correct?
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Old 08-24-2006, 12:45 PM   #18
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You may have a bad MAP sensor. On the 92-95 L67'*, it'* sole purpose is for a boost indication (gauge input), and is not used for any PCM functions or calculations.

This is assuming you have no belt slip (which is very hard to detect) or a vacuum leak.

Your troubleshooting steps at this point would be:

1. Take a pic of the tension scale on your SC belt tensioner and post it here.
2. Get a can of Belt Dressing and spray it on the belt to see if it changes anything.
3. Using a can of carb cleaner at idle, spray it lightly on every vacuum connection and interface point (around the base of the SC, the seal of the BCS, all fittings and manifolds, including the vacuum accumulator on the firewall between the WS wiper motor/gear assembly and the maxifuse relay center---pay close attention to the vacuum fittings underneath).
4. Consider a new/wrecker MAP sensor for troubleshooting, or borrow/swap/troubleshoot with another member.

Ignore how the car 'feels'. Post results based on boost indication only.
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Old 08-28-2006, 08:48 PM   #19
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ok, sprayed all the vaccuum connections I could find with carb cleaner but created no change. I checked the tension of the belt, but do not notice any signs of slippage although I do have a rythmic squeak when not under acceleration. (Will attach pics of belt tomorrow.) That just began occuring and is not related I am sure. The last thing I have to check is the map sensor. I have a friend with a 95 Park Avenue Ultra. Does it have the same MAP sensor as the '92 SSEi? Also, I believe the MAP sensor is above the TPS on the throttle body. Is that correct?
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Old 08-28-2006, 11:17 PM   #20
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The MAP sensor is NOT in the TB. And the PA may not have one. Only full-OBD2 cars got them, or OBD1/2 (full obd1 or hybrid 94/95) got them IF they have a boost gauge.

It is the rectangular box behind the SC, mounted to the fuel rail. It has a vacuum line and electrical connector.
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