SaabCentral Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
57 Posts
Discussion Starter · #1 · (Edited)
hi,
my turbo/apc guage needle never goes higher than halfway through yellow is this a problem ??? the car doesn,t seem to lack power but i,d hate to be missing out on horsepower.
thanx in advance for your advice.
it,s a 1995 9000cse fp turbo auto by the way

george :D
 

·
Registered
Joined
·
1,220 Posts
The turbo guages are notoriously unreliable, but what your describing sounds like you are getting base boost only. When you are accelarating hard you should really feel like you are being shoved back into the seat. Accelaration should be fierce (and I mean fierce) when accelarting through the gears. If you can't tell when the turbo has kicked in, then get it checked.

The obvious things to check are the APC control valve (above radiator), wastegate control rod, turbo dump valve and associated vacuum pipes.

Use the search feature as well to look up about the wastegate (I can't remember the exact terms as my brain is mush at the moment).

Kenneth
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #3 ·
when should the needle hit the red ? i assume it is not when revving out of gear but when accelerating hard while driving. i drove a landrover before so to me the 9000 seems rapid anyway but i want it to be right.
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #4 ·
i have a boost guage that i,m not using in my garage should i set it up temporary to see what pressure i,m getting ?. if so what pressure should it reach in psi.

thanks
 

·
Registered
Joined
·
70 Posts
Funnily enough mine is doing the same. I took it to a local saab specialist, and they said this was ok as the gauges are not really accurate. I had a go in a friends FPT, and his was noticeably quicker and boosted to the start of the red. I also noticed that the fuel consumption figures on his computer were loads better than mine too - related perhaps?

I definately can't feel the turbo kicking in, but when I release the accelerator it does pick up marginally. Does any one know of any specialists in Scotland that could check this out properly?

Or has it been de tuned to save the auto box? (mates was auto too)

Cheers

Pete
 

·
Premium Member
Joined
·
31,228 Posts
Sometimes boost variability is merely a function of your gas octane. With 87 octane (our regular) I'm not able to boost much more than 1/2 into yellow. But with 91 or higher, I can easily boost into the red, although I'm not a speed demon so I've yet "explored" the full potential of my FPT.
 

·
Registered
Joined
·
70 Posts
Checked hoses going to APC today. The return pipe appeared loose at the trunking going to air filter, and on further investigation I found the small pipe had almost broken away from the housing. I have effected a very temporary repair and took it for a short drive - it appears marginally better, but I will have to effect a proper repair, or get a secondhard part to discount this as the problem.

This fault must have existed when I bought the car.

Pete
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #10 ·
this is bizarre i also checked hoses etc today and believe it or not i also found the small spigot on top of the air inlet duct broken. i hotglued it and it appears to be holding but unfortunately it made no improvements to my base boost only problem. so i,ve checked the hoses i,ve checked the waste gate rod how do i check the apc valve? i want full boost.:(
 

·
Registered
Joined
·
57 Posts
Discussion Starter · #12 ·
ha ha yes maybe it is....i,m tempted to shell out for a manual controller but i,m not sure how to connect it up! are there any fitting procedures on line anywhere
 

·
Registered
Joined
·
3,938 Posts
Boost gauges are not accurate. However, the trionic cars should put the boost gauge into the red at maximum engine loading which occurs at wide open throttle around 2,000 to 3,000 rpm in 3, 4 or 5 th gear.


Autobox cars have limited boost in lower two gears, manual shift cars are boost limited in first gear. All trionic turbo 9000 are tire limited in the lower gears anyway! Maybe with Bridgestone Pole Position S-03 tires you might get enough grip to hold full torque.

Max torque occurs at around 1,800 rpm at wide open throttle on these engines. Older APC cars don't boost into the red (SPG or Carlsson cars maybe excepted) and max torque is developed at 3,500 rpm also at wide open throttle.

Anything less than wide open throttle and full engine loading will not allow the engine time to develop full boost pressure. In fact, it can be tricky to find enough open staright and unoccupied road to use more than a second or two of full boost!!!
 
1 - 13 of 13 Posts
Top