Date: Fri, 26 Aug 2005 18:25:23 GMT From: Johannes <johsnospam-gets-snuffed-sizefitter.com> Subject: Re: Any advice re high mileage Saab 9-5 2.3 Hot Aero?
Gary Fritz wrote: > > > Are there any particular "gotchas" I should be on the lookout for with > > this particular model? > > I have a 2002 9-5 Aero Wagon. My experience (which some here disagree > with, but I'm not sure they've driven the US version of the Aero) is that > the Aero is a pretty disappointing car. > > The HOT engine can crank out an amazing amount of power. The trouble is > that it very seldom delivers it when I need or want it. > > I've been told by 3 different Saab mechanics that the Aero's turbo is a > very large turbo with a lot of inertia. Because it is large, it can pump > a lot of air through the engine and deliver a lot of power. But because > it has a lot of inertia, it takes a very long time for it to spin up to > the point where it gets into that power stage. > > In my car, there is a lag of 1.5-2.0 seconds from "hit the gas" to "full > turbo power." I've driven 2 other Aeros and they were similar. Doesn't > matter how fast you're going -- you can be cruising at 4000 RPM and hit > the gas, and the power doesn't fully kick in for over 1.5 seconds. > That's a long time to wait for power if you're trying to pass on the > highway. It's an eternity when you're trying to dart out of a side road > onto a busy street. > > Furthermore (again according to the 3 mechanics), because of emission > controls, the turbo apparently somehow spins down EXTREMELY rapidly when > you let off the gas -- faster than I can shift. (I don't see how this > high-inertia turbo can spin down that fast, but it does.) This means > that you face the same turbo lag on EVERY shift. Because the car does > have some power before it maxes the turbo, and because you accellerate > VERY rapidly once you finally spin up the turbo, and because you have to > go through the same cycle on every gear, you end up spending VERY little > time in the "full power" mode. You spend a lot more time in the "geeze > when will this tank finally start moving" mode. It's maddening. > > (My car has a 5-speed. I believe the engine may be better matched with > an automatic transmission, which would allow the engine to keep torquing > more steadily than a manual, but that's a guess.) > > You'll also find the Aero has (comparatively) very little power off the > line -- the turbo isn't spun up. In 3 years of pretty aggressive > driving, I have NEVER ONCE "burned rubber" in my car. It CAN'T. There > isn't enough power there, from a standing start, to do it. There's > barely enough to get the car moving quickly without choking. Pretty > pathetic for a "sporty" car that was advertised to have a ruler-flat > torque curve all the way down to 1400rpm. (I test drove a 2003 9-3 once > and ACCIDENTALLY chirped the tires several times. After driving my Aero > I just wasn't used to that much torque off the line.) > > If you spend all your time on a dynamometer -- like the ones they used to > generate those torque curves -- then the Aero's engine is a monster. The > steady-state power delivery is amazing. It would be terrific if you > climb a lot of mountain roads. It's pretty good for highway driving. > But if you spend a lot of time driving in town, frankly I think it sucks. > > If I'd understood this before I bought the car, I wouldn't have gotten > the Aero. I would have gotten the regular turbo 9-5 and probably would > have been a lot happier. > > Gary Hmm. Perhaps it's not such a bad idea that Saab/GM has now come up with a new turbo charged 2.8/6 engine with the same power 250bhp.