Just Bought a 97 Legacy 2.5 GT need some help

im a former grand am owner, and ive been through alot with that car replacing nearly everything, headgasket, tranny, struts, wheel bearings, gas lines yadda yadda, so i can do work on the cars, i can do good work but im not great at diagnosing them. now i got sick of putting so much cash into this car and went out and bought this nice condition subaru legacy GT, 117k auto trans miles now the car runs great and drives nice, it has a few minor problems. the guy told me it needed a tune up and a new knock sensor. the car drives great but when i try to floor it (WOT) it stutters and practically dies, but it will slowly climb to 3k and WOT it flies. now the idle is a bit rough from time to time but mostly smooths itself out. my old grand am had this same problem, i replaced map, maf, tune up, and IAC and that fixed it, i dont know if it would be the same for this car. now i was kinda nervous buying a foreign car, but hey i needed a new car and AWD for winter sounded nice. what should i be worried about with this car and what might you all think the problem for the stutter is? all help Appreciated. ty

Read through the link below and do everything in the MPG section

Second Generation Legacy Engine FAQ

As far as what you should be worried about on these cars... Have the head gaskets, timing belt, tensioners, and water pump been replaced yet?

If not, keep an eye out for the gaskets failing, it's a common problem on our GT's. Most fail between 100 to 120k miles, but some last much longer. Mine lasted 167k miles and some people have never had them fail. It just depends on how well the car was taken care of and how it's been driven.

If the timing belt hasn't been replaced it should be asap, as the service interval is at about 100k miles. And while you're in there you should replace the tensioners, idler pulleys, and water pump so you don't have to go back in later on. It's kind of a pain to do.. If done right, it'll only take a few hours though.

Or an hour if you know what you're doing

Unplug you MAF while the car is running, if there is no change in idle then the MAF is most likely bad. Could also be a know sensor, but that usually just makes the car run rough. Also it never hurts to clean the IAC (there are a few threads with how-to's on this).

Agree with Kenny on the things to watch out for.

Originally Posted by broknindarkagain

Or an hour if you know what you're doing

Agreed. It took myself just over an hour to do it.

Originally Posted by Kennyfvholla

Agreed. It took myself just over an hour to do it.

But you had your engine out of the car right?

If the engine is out of the car, its A LOT easier and quicker. I can do it in about an hour without removing the radiator ^_^

awesome well i didnt know these cars were notorious for bad gaskets, well my old car did anyway so oh well. now are motors hard to work on on this car? im going to get a manual for this car tomorrow. and do a tune up and clean as much as i can along with replacing the rear diff fluid. now for replacing the tranny fluid and the filter, should i replace with half old oil and half new or filter and use all old or just strait new? thanks for all the input and very quick response too =] thanks all!

Go back to that link I posted earlier. There is a link to download the factory service manual.

As far as your transmission goes, just drain the pan and refill it. Do it 3 times, drive a few hundred miles between each time. On the last fluid drain, replace the filter. Whatever you do, DO NOT flush the transmission....meaning services like TTech or similar things where they hook your car up to a machine to flush the trans. Only do a Drain and Fill on it.

ok now when u say drain and fill, fill with new or the old fluid but cleaned?
also are these cars odometers reverse-able? because im not to sure a 97 could only have 117k on it. i meen the body itsnt terrible, very little rust.

My 98 only has 130 on it. I've seen them with less than 50k before.

Odometers aren't reversible. You can switch out the entire gauge cluster for a lower mileage one. If you suspect this is the case, run a CarFax report and check mileage in the cars history to find out if this happened or not. A perfect example I can give you is my old 95. Odometer said 104k when I first bought it. I ran a car fax report later on to find out that the car has well over 200k on it. Someone at some point in time switched the gauge cluster for a lower mileage one.

Fill the trans with new fluid on each drain and fill

Originally Posted by broknindarkagain

But you had your engine out of the car right?

If the engine is out of the car, its A LOT easier and quicker. I can do it in about an hour without removing the radiator ^_^

Nope! Cuz after I got the engine back into the car and everything hooked back up, and I mean EVERYTHING, the water pump started leaking because of the crappy felpro gasket.. I then just tore out the radiator (and if I had a grille it would be removed because it gives you a ridiculous amount of access) and then had at it.

Originally Posted by severedevil

awesome well i didnt know these cars were notorious for bad gaskets, well my old car did anyway so oh well. now are motors hard to work on on this car? im going to get a manual for this car tomorrow. and do a tune up and clean as much as i can along with replacing the rear diff fluid. now for replacing the tranny fluid and the filter, should i replace with half old oil and half new or filter and use all old or just strait new? thanks for all the input and very quick response too =] thanks all!

New filter, new fluids. Do EXACTLY what Brokin said to do about this.

The cars are easy to work on, but depending on what you're doing they can still be a complete pain if you're not used to working on them. Get the Haynes repair manual and use that in conjunction with the Factory Service Manual, that's what I did.

Also if you live in NY and have very little rust on this type of car, you're car has definitely been taken care of and very well could have 117k original miles. I used to live on Long Island, and I know how driving a car year round up there takes it's toll. Crappy, beat up roads, and the winters with all that salt...

ok 2 codes popped up,
P0325 - Knock Sensor,
P0341 - cam pos sensor,
now i ordered a new knock sensor because the motor has no knock and its what i was told was wrong with it. adv auto wanted 80bucks for it, 17.99 on ebay. now i was also told that the knock sensor can trip the cam pos sensor, am i wrong?

I would start with the knock sensor.

However, I don't think the knock sensor will trip the cam position sensor code as well to be honest with you

so how should i rig a CAI in my car? the Weapon R doesn't seem to fit but i can make it and will try