SaabCentral Forums banner

Low boost help!

919 views 8 replies 5 participants last post by  Flarty 
#1 ·
I have searched all the other low boost threads but not found the answer to my problem.

Basicaly my 9-5 aero boosts 75% into yellow and dosent reach the start of the red untill around 4k rpm when it reaches the start of the red there is a noticeable increase in power.

having watched videos on youtube it appears it should reach full boost much quicker than 4k rpm

I have tried blocking the top pipe on the evap valve which made no diffrence.

i have reset the ecu which again made no diffrence

i have no cel lights

car was serviced a few months ago using genuine saab parts.

other than the low boost it runs perfectly fine and it does eventualy reach full boost but not untill 4krpm, the car is run on shell v power.

i dont know what to try next i cant hear any leaks as i have an open airfilter.

its really bugging me now any ideas what to try next?
 
See less See more
#4 ·
You do know that the "boost guage" is actually a torque request meter and can be adjusted by a Saab Mech with Tech II?

You can have it adjusted to read in the red all the time if you want........

The only use for the guage is if you use it to spot any changes, i.e. if it always went into the red - BUT - now doesn't............. then something has happened.
 
#5 ·
it still goes to the start of the red but not untill 3.5-4k i havent driven the car hard for a while but im pretty sure it used to pretty much instantly go to the start of the red before 3.5krpm now it seems to take longer to build up the boost.
 
#7 ·
Flarty, its cold in the UK at the moment meaning the air is denser for the intake system meaning less boost is needed to produce the same power output. You will probably find it will boost higher in hot weather due to thinner air pressure. As Chris has already mentioned the boost gauge is programmable so isn't really a true reflection of boost pressure but just a way of noticing if something is wrong.
 
#8 ·
well the car seems to be running absoluetly fine other wise, i could evern just be me getting used to the power im just pretty sure i used to get full boost before 4k rpm, i cant do much at the moment because its raining over here so everytime i try and give it any serious beans when the boost kicks in it trys to drive into the kurb, it hasnt had a good thrash for a while im hopeing it will adapt when we get some dry weather and i can give it a good spanking.
 
#9 ·
Small update... had some dry weather this week meaning i could give it some abuse...its deffinetly improved! it started going to the start of the red again without fail but not before 3.5krpm, i now have to hold on again when i boot it in 2nd gear
 
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