About my 2004 Subaru WRX STI
Asked by Guru9CWZJ Jun 24, 2017 at 09:32 PM about the 2004 Subaru Impreza WRX STI Turbo AWD
Question type: General
I have a 2004 Subaru WRX STI and this is a 2 part question. It has 38k miles
on it and i was wondering do you really need 93 octane will 91 be enough if
you dont have 93 in your area, and next question is when im driving it can i
have fun with it? Like give it gas and have fun with it once in a while without
hurting the car. And 1 more question SORRY! When im backing up into my
garage when i brake there is a squealing noise is that normal?
4 Answers
If you can get 93 octane try it and compare the performance to 91 octane. You may get more boost with 93.
TheSubaruGuruBoston answered 7 years ago
Wow...finally three great responses w/o unnecessary nonsense! I'll add that it would be very rare indeed to have 13 yr old rear rotors that DON'T squeal! The older 2.0T is sturdier than the subsequent 2.5T, so take care of it with clean higher vis synth to protect the turbo bearings from overheating the oil and burning them. I, too, wouldn't worry about 91 vs 93 oct. Just don't use 89.
I saw this and i need to answer lol. Congrats on getting a STI! they’re a whole lotta fun. first question: Since the engine has forced induction (the turbo) it is high compression rate meaning the air / fuel mixture is being compressed in a much smaller space making the pressure high. if you have gas that is not as resistant to knock it could cause premature ignition which is knocking and can mess up your engine in the long run. If you’re only 2 octanes lower once in a while don’t worry about it but use the 93 as much as you can. Question 2: Of course you can have fun with it dude!! I mean don’t floor it constantly but give it the beans once in a while, it’s a performance car! Do some power shifting and some pulls that’s what it’s built for. In fact, driving it hard once in a while is good for your engine as carbon tends to build up in the fuel injectors and giving it some gas will usually clean the carbon. Question 3: I’d say squeaking brakes is normal as long as the brakes have holes in the rotors. these are called drilled rotors and they come stock on STIs. the holes are to dissipate heat better than the conventional stock brakes as you may need more brake power as the car offers more power than normal cars. So the squeaking is really nothing to worry about unless they’re constantly doing it whenever you brake.
TheSubaruGuruBoston answered 4 years ago
Q2 I wouldn't agree with the carbon buildup scenario in these modern motors. I also would NOT try to shift without declutching as the trannies' syncros aren't the strongest. Have fun...but realize it'll be temporary.