legacycentral bbs

Ok guys i am a newbie to this site but i have been reading it for over a year now and i think you guys might be the only ones to help me with my 1990 legacy.

Ok i'm gunna get straight to the point.

So i'm driving my car around enjoying my subie exhuast (muffler actually)and stop at a light. I havent floored the car yet this morning so i think why not enjoy myself. So i slowly just go off to a slow start and work my way up to 4000 rpms in first. What the fck! I get to 5000 rpms and the car refuses to rev past it for like 4 secs but slowy catches and gets past and straight to 6.

Now this happens to me in all the gears. Does anyone know why my car refuses to rev smoothly through 4500-5500 rpms? One of the guys i take my subie to says the car is just losing power becuase i do have 195,000 miles on it. So he said do a tune up. So i bought a fuel filter, new plugs, and i'm going to get some spark wires soon by ngk the v2's. Should this help the car out in that area? I also started using 89 octane fuel and stopped using shell cus i heard they suck. Also put in some octane booster.

Can someone please tell me what is up??! I appreciate it.

dont forget air filter!

Yeah i did that. Got a fram filter. Might go with a K&N soon as i figure out what is wrong.

Started using 89? What were you using before? 87? That should be fine. Octane is not a performance enhancing thing. It is a detonation preventer. Without a super high CR, you don't need that protection and are wasting your money. Run your car on 87

thanx

I say a possible bad O2 sensor. My Legacy has never done what you described, but my XT has and a new O2 sensor fixed it.

Do a sea-foam treatment, and see if that helps.

I'd be willing to put heaps of money on it being something electrical. Plugs and wires maybe, but also sensors. Something giving a wierd signal and causing the ecu to pull timing. O2 sounds like a good guess to me (might as well replace that old unit anyway, a 323 one is only 20$), i might try disconnecting the knock sensor (resonant frequency?) maf (easy to check!) if that doesnt fix it, and checking out my battery wires.


If bumping up the octane helps, run some sea foam, carbon buildup may be causing detonation (via preignition or increased cr). It may not help even if 89 does (detonation could be from a lean condition in one cyl, or something like that), and i myself am skeptical of the stuff.

I know it's blasphemy and whatever, but i strongly disagree with what monson says about 87. With almost 200k on the ticker surely carbon build up has raised his cr a bit, but beyond that, i would be hesitant to run 87 even on a new bc legacy. Our fueling is good, but dated, and 9.5:1 is pretty high for 87. On top of that, the ecu is going to not see any knock, so on hwy driving the ecu can run the timing out a little further, with nothing but benefits.

I'm not an expert.

Scot has a point about the age, but the owner's manual states that 87 is fine. I'd see if you get better power with the higher octane and if you do, stick with it.

Steve

holy crap you guys know your shit. Thanx a lot. yeah i was also thinking that it might be something electrical.

OK just a little update here. My mechani called and leave e a very brief message.

"Your car has a problem but i can't tell you over the phone. You have to come and see this for yourself."

Shit.

Rat in the intake?

OK my dad got back to the mechanic and this is what he said.

He did a tune up and everything and found that the car was still experiencing the problem described. So he was looking around and found that the crankshafts teeth were all grinded out and messed up. So now he says he has to take out the crank shaft and see if there has been any internal damage made. Hopefully there won't be any becuase if there is i'm gunna be without a car for a long time.