I absolutely love my WRX Wagon - the only problem I have is with the power output... Sometimes this wagon just kicks butt and screams... Other times it feels like it doesn't have a turbo and I can't get to 60 any faster than a (gulp) Civic...

Now I've unplugged the battery and let it sit for three hours. Then took it for a wild ride - it performed like a dream - power on demand at every turn. Even so, I won't do this to my WRX all the time because I want it to last and I seriously do take care of it.

And hense the prob: I drive to work (20 miles) and back each day never going much more than 5 miles over the speed limit. This car is a pleasure to drive even if you are not gunning it at every turn. So after a few days of very gentle driving, the ECU appears to be tuning to that gentleness and then when I want the power, it just doesn't seem to be there.

Wish there was a switch: [Gentle] and [Kick Ass] so I could toggle it when I wanted...

Cheers!

weather has a lot to deal with the way your car performs, i can tell a difference when the gas tank is full or not, and sometimes you just get used to your car...i bet if you put it on the dyno you would find out that most of this ECU learning to be gentle is in your head

Right - I can tell when I've got four people in the car, or the tank is at half, so on and so forth...

Where I live, it's generally 20'F to 35'F in the winter, and 90'F to 106'F in the summer. Right now this week it's been around 102'F all day long. So heat may have something to do with it.

It is just a pisser to start off from the line and watch the first gear wrap to 7000 rpm and not get feel the pull. Each time it's different. Some days it kicks butt, some days it feels like there is very little turbo boost.

Ah well.

Don't just the battery sit for three hours, press the brake pedal to drain everything. Follow proper train method after reconnecting. Let idle for a few cycles, turn off, turn back on, drive like you stole it, turn off. But search for the proper ECU reset for the full instructions. This has made a big difference for me. Also don't be reset happy because the ECU is constant learner anyways. After some serious highway miles the car's very happy.

Infymus

I have the same problem too, but I think the problem has a lot to do with the gasoline being used. I have seen a major difference 10-20 miles after a fill up. I try and purchase may gas from the same Mobile station which I seem to get the best performance from. I think part of the problem is some stations may not be selling premium gas when they say they are.

Also where I live we are required to use a reformulated gasoline to cut down on pollution, but the next county over isn't. Last week I was in the other county when I filled up, and now my car has felt so strong this week that I think I am going to travel the extra 15 miles to get my gas from now on. Also the weather this week as been in the 90's with high humidity and my car still felt stronger than normal.

You know I've thought about that too... I always buy my gas at Chevron - and always the same station right by the house. It's a new station - only been around for about five years (so there are no old tanks, no gunk buildup).

The station does use that one-hose-for-all system and that makes me wonder. What if the guy before me was using unleaded-regular? Does the hose suck it back into the tank, or when I go to get premium, do I get a unleaded-regular until what is in the hose empties into the tank? Don't know. The system is one of those "always on until you hang up the nozzel" deals, so you can't just click it until it stops then dangle it to get the last drop.

I could use Chevron's Techron addative, but I've heard that it's not good on new engines (mine has 2000 miles now). Rather not add anything and risk hurting the engine.

i find just the oppsit is true ... after an ECU reset ..less power

which makes sense as the ecu has not set a long fuel adjustments.. so it runs rich to be on the safe side

i find that after 650-700 miles the power gets much better

i also buy only 1 type of gas from one vendor..

also try the 3/16 mod...

With the stock ecu, some gas brands would "feel" really good, and some would "feel" much less powerful - I think gas quality (and definitely octane) has a huge effect on how the ecu performs. Try adding a gallon of Toluene into a tank for an octane booster - you'll feel much less difference in day to day driving (no more slow days).

Two words: Boost Monkey