1985-1998 [Subscribe to Daily Digest] |
![]() | [Main 9000 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Depends- Posted by Ari [Email] ![]() ![]() In Reply to: thanks, another 1 tho'!, paulmanchester, Tue, 18 Jun 2002 15:41:14 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Are you getting a variation in maximum boost from day to day, OR for the same boost, does the car feel faster one day to another?
If you're getting variation in boost, there could be a bunch of things to look at. The APC dials back boost if it detects knock. Knock is caused by lots of things, like grade of fuel, timing, engine and air temp, load, etc. So on a hot day, you might knock a little, and the APC will dial back the boost. Or you might be on the hairy edge of detonation due to the fuel, and some days it does (full boost) and other days not.
If the boost gauge goes up the same, but the car feels slower some days, it could be a (different) bunch of things. The biggest one is air temperature and humidity. Hotter, wetter air has less available oxygen per cubic inch than cooler, dryer air; and turbo engines are very sensitive to oxygen density. There is a noticeable difference in performance between a cool, dry day (say 40-50), and a hot, humid day(80 or 90 and sticky). Also, the intercooler is less effective on hot days, or after the car has warmed up, or has been heat soaking on a broiling parking lot.
Lastly, you might have a problem that's intermittent. A faulty AMM (air mass meter) comes to mind. A bad AMM causes massive hesistation, but some days it might be fine, others, not so good, as it works it's way to total not so good. Or an O2 sensor that's getting old.
Good luck!
posted by 140.157.4...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |