Saabscene Saab Forum - Saab Technical Information Resource banner
1 - 11 of 11 Posts

·
Registered
Joined
·
252 Posts
Discussion Starter · #1 ·
Hi,

Ever since replacing my blown turbo with one from a breaker (reputable SAAB specialist) , the whistling noise it makes as the turbo spins up is louder than it used to be with the old turbo.

As I have a CSE 2.0 EcoPower (LPT), there is no boost gauge so I can’t compare readings. I used Bill J’s guide for the removal/replacement procedure, and at the end he mentions something about adjusting the base boost if necessary. Does this apply to my LPT??

Any other suggestions as to what might be causing the extra whistle?

I’m not 100% convinced that she pulls as well as before – but I’m not sure if that’s just me being paranoid!!

Thanks
 

·
Registered
Joined
·
8,216 Posts
Originally posted by Jules:
[qb]adjusting the base boost if necessary.  Does this apply to my LPT??[/qb][/b]
Yes. See here for the correct setting. I think the '94 and '95 ones, although not in the table, should be around 0.35 bar base boost.
 

·
Registered
Joined
·
252 Posts
Discussion Starter · #4 ·
Thanks for the clarification Bill.

While I’m here, section 4 of your turbo removal guide states that “On all cars other than LPT models, locate the BPC valve on the radiator……….”.

My 94’ 2.0 EcoPower has a BPC valve. (She’s definitely an LPT: confirmed by the VIN checker on your site, from Southampton SAAB by the registration number, from an engine number of B204Sxxxxxxx and no turbo badging or boost gauge)

Interestingly enough, the replacement turbo I got from the breakers was obviously taken from a car without a BPC valve as there was a short length of pipe connecting the compressor nozzle to the wastegate actuator nozzle (which I removed and connected to the BPC valve).

The physical appearance of both units was otherwise identical. The turbo itself is a Garret with both oil and water cooling, which I guess makes it a T3?

Is my car just a later model of something??

Also, what does BPC stand for?!
 

·
Registered
Joined
·
454 Posts
1993/4 LPT's have the BPC but not the intercooler, 95 LPT's onwards have the intercooler but not the BPC. With the BPC you get overboost protection, with the intercooler thay changed the ECU to keep the same HP as an LPT without, sad really.
 

·
Registered
Joined
·
94 Posts
I wish my Carly would whistle.I love whistling turbos,sound like jet aircraft taking off,but I have never been lucky in that dept.Neither of my two 900 turbos ever produced much in that dept,but,like the Carly there was nothing wrong with the boost! The Daf lorry I drive occasionally screams like a banshee however--bliss!
 

·
Registered
Joined
·
494 Posts
personally, the only real 'whistling' sound i have run into came from a loose intake hose, between the intercooler and throttle body. check all your hoses as mentioned, make sure everything is seated properly and fits tight.

my '92 c900 T does not produce much in the way of whistle, but i certainly can hear an audible 'whossh' type sound as the turbo spools up (never heard much before the stage1 upgrades though)
 

·
Registered
Joined
·
1,749 Posts
My old 9K used to whistle - well almost scream actually - especially when cold. It also had a faulty DV, so you used to get that chopping noise from turbo really loudly. Although it did sound quite banzai, it turned out to be the bolts from exhaust manifold to head being loose, and tightening them quietened it down.
 

·
Registered
Joined
·
252 Posts
Discussion Starter · #9 ·
Ahh - Ok, thanks for clearing up the BPC valve business: correct, I have no intercooler so that makes sense.

I guess as I've had all the hoses disconnected to replace the turbo I just need to go around with a spanner and screwdriver and tighten everything up, now that everything's had a change to "bed in" as it were.

Another question: How come I can't hear the Turbo wind up with the car standing stationary and me revving the engine from under the bonnet? Is there some kind of inhibitor to prevent it boosting when not actually driving?

Cheers
 

·
Registered
Joined
·
461 Posts
You can't get the turbo spinning up while standing still -something to do with backpressure (can't remember).

If you want a turbo whistle, and other sucky, burbly, whooshy noises that you don't have currently, just fit the JR induction kit like I've got on my Aero, and you'll get them all a-plenty.

Carl
 

·
Registered
Joined
·
222 Posts
The turbo does not spin up when the engine is not under load (i.e. driving the wheels) because you are not really burning very much fuel to turn the engine, even at red line revs. Little fuel burned = little exhaust gas produced = little boost for the turbine blades = no spinning turbo noise.
Push the accelerator down in the car in neutral and take note of how far you push it before it red lines the engine (and the ECU stops putting more fuel in) and then push it the same distance down when driving and see how little boost it produces.
 
1 - 11 of 11 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top