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Discussion Starter · #1 ·
Some time ago I posted about my aero turbo boost pulsing under pressure, especially going up hill. Occasionally this would be accompanied by a 'through the window' experience as the engine management tried to prevent the over boost
. It was recomended that I try an adaptive run and this sorted out the shut downs (thanks to the guys that suggested this
), but I still have the problem with the pulsing boost, but I have been living with it for now as I don't have the cash for the most likely suggested cure, a new £120 BPCV, especially after christmas and new year (Happy new year by the way). I can feel the power drop off as the pulsing starts and I just happened to read in another post in a search of this forum that someone had recovered a problem with their BPCV by giving it a blast through with carb' cleaner. Do you think this is worth a shot with mine? Anything to be wairy of? Is there one port that I should clean it through from (I don't have much idea what goes on inside this thing so I don't know if there are any delicate parts or oneway valves)?

Cheers for any advice
Kev
 

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Discussion Starter · #3 ·
Hi Ash
I'm not sure it sounds like the same thing. I don't have a problem achieving full boost...its more a problem of a slight over boost but rather than the BPCV controlling the turbo boost smoothly, it does so in pulses so that I can hear the turbo pulsing and spooling up and down slightly. The result is that I get more power if I accelerate with the boost only at the top of the yellow as there seems to be an even use of the turbo, whereas flooring it seems to result in the turbo constantly being pulled back out of the red and loosing some of its momentum, with the resulting loss of power. Not that its a dead loss or anything. It is still a respectable turn of speed, its just a bit frustrating that when I really want that bit extra and floor it I end up slowing down slightly. Its just my impression of what is happening, but it has been previously suggested that this may be a problem with the BPCV itself not operating correctly and someone, having had the same probelm in the past, solved it by replacing the BPCV. Being a cheapskate I thought I would try a bit of cleaning prior to buying a new one

As a related question...I may end up replacing the BPCV and was wondering if all the saab turbo BPCVs are the same? I have prices from some saab breakers of about £25 to £40 plus VAT and p&p for BPCVs but they don't spsecify if they have been removed from an aero or not?

Cheers
Kev
 

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Hi Kev,


I've replaced one BPCV on my Aero about 3 years ago (about 40 quid from a breakers, DCA in Reading), and think it may need replacing again. I have similar symptoms to you, the pulsing and occasionally the overboosting (with associated-driving-into-a-brick-wall-cut-off).

I think the BPCV itself is the same between Aeros and FPTs, after all it's only a valve responding to what it's being told by the engine management system.

As to cleaning it out with carb cleaner... I've no idea!

cheers,

Ben.
 

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From what I remember reading here, the consensus is that if the BPCV is a problem, cleaning it will often solve it temporarily, but it usually isn't a long term solution.

My guess would be that perhaps the solenoid coils overheat if the mechanism is sticky?

But I don't believe it will do any harm. One of the outlet nozzles has a throttling collar in it, so make sure that is clear.
 

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Are 9-5 Aero BPCV's the same as 9000 Aero BPCV's?

I recently changed mine (9-5) for a genuine new one and as far as I can recall it was only about
20-odd quid. At that price it hardly seemed worth fiddling with the old one. I can check the part number of the one I have if there is any interest?
 

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Originally posted by SJ:
[qb]Are 9-5 Aero BPCV's the same as 9000 Aero BPCV's?[/qb][/b]
I don't know!

Originally posted by SJ:
[qb]I can check the part number of the one I have if there is any interest?[/qb][/b]
Yeah, why not. THe duff one from my 9000 Aero is sitting around at home, so I can check the number without even opening the garage or the car bonnet! In fact my girlfriend is sitting around at home as well so..... (quick phone call) ..... Saab part no. 7485576

Was that 20-odd quid for a genuine Saab one, from a Saab dealer? My recollection is that they wanted 100-something quid +VAT for a replacement for my 9000 Aero. I'd cheerfully pay 20 quid!!

cheers,

Ben.
 
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