octane boost and turbo????

[Motoxdude6]

so i use premium gas in my car 90 octane but with each full tank i add a bottle of STP fuel additive octane booster. the past few weeks i have noticed a squeeking coming from the engine around the turbo/power steering area. im pretty sure its the turbo. its a squealing noise that only happens after i warm up my car from a cold start. while its warming it doesnt do it, but when i start driving it will do it for about 10-15 minutes max then it fades away and wont do it again till i repeat the proccess from cold start. i really dont think the STP additive has anything to do with it, but i would like to know what others think about this situation? im going to make an appointment with subaru and take it in cause if it is the turbo its covered under warranty. any kind of help or input will be appreciated. thanks. and if i get a chance i will try and record a video of it while its making the sound but its hard to do that cuase im driving the car.

[MainFrame]

Well.. premium gas in TX is 93, I've never seen a station selling 90 octane? And octane booster doesn't really do anything at all, so I would not suspect that's a problem.


Squeaking could be a lot of things, usually belts. I've also hears IWGs squeak (not squeal). It's hard to say without knowing what the "squeak" really sounds like.

Usually a blown turbo will make your exhaust smoke like crazy.

[nsibanez]

try recording the squeak on video and posting it. as with any noise complaint, no one can properly give you a diagnosis without hearing it themselves. ive heard a squeak coming from maybe the turbo sometimes after very little throttle, and then letting off. but its prolly just the waste gate and figure its normal....its a subaru and does make some weird noises sometimes

and usually premium fuel is no less then 91 grade

[11blackSTi]

Octane boost is a waste of money. Look for higher than 90. Yeah get the squeak looked into if it is under warranty.

[MainFrame]

I used to have a sound when letting off the gas that sounded like crickets chirping.. for the longest time I thought it was the IWG flapper, then one day I discovered it was my muffler scraping against the heat shield, and the noise traveled up the exhaust. Took a pry bar to it and never heard those damn crickets again.

[nsibanez]

I used to have a sound when letting off the gas that sounded like crickets chirping.. for the longest time I thought it was the IWG flapper, then one day I discovered it was my muffler scraping against the heat shield, and the noise traveled up the exhaust. Took a pry bar to it and never heard those damn crickets again.

you know what, since you mentioned it...ive not heard it since i adjusted my exhaust either

[Kwrxp]

Yeah, find a higher grade. There has to be a 92-93 some where around you. There are also phone apps that will find gas stations that sell higher grades, because 90 is pretty much mid grade.

[SD_GR]

The car will run fine on 91 indefinitely, and lower in a pinch.

The squeak is not related to the fuel.

The additive is worthless.

Check the auxiliary belts and rollers.

[Motoxdude6]

93!?!? Wtf every gas station I go to I used the most expensive and the label says 90 on it. Are they screwing me? Cause it's like that at more than one gas station I go to. I know the turbo is fine cause I'm still boosting what it sounds like is a dry bearing that needs grease in the turbo. Could be a belt yea but I will be pissed if it is cause those are not covered warranty. Cause Subaru charges rediculous amounts for that simple ****. I don't expect octane boost to do a whole lot but it does cleans injectors and what not doesn't it? I have appointment at subaru on Thursday to get car checked out.

[UEDan]

Turbo and PS pump is pretty far apart.... But from what you're describing, you have a PS problem. Check the reservoir for bubbles at startup and check if the PS hardline is vibrating when the noise is present.

Posted from a fone.

[Sinister]

if you're under warranty... go get it checked.

And you're not calling the plastic snail the turbo, are you? That's the vacuum pump

[nsibanez]

the belts on subarus are easier then hell. try doing one on a tc without removing the passenger front wheel.
the hardest part is the a/c belt because they need to be cut and use a belt puller to get on. theres no tensioner and its a stretch type belt

[Motoxdude6]

no no i know what the turbo looks like i know im noob but im not stupid lol. ok aside from the squeeking problem im having cause it sounds liek i will only get the answer i want from subaru. i need to find higher octane gas. all the gas ive been buying is 90 octane and thats the highest ive found. anyone have any idea on how i can find higher octane gas in lubbock, tx?

[Anub1s]

Might be because of your proximity to NM that you have lower octane there. What is the elevation in Lubbock?

[MainFrame]

i need to find higher octane gas. all the gas ive been buying is 90 octane and thats the highest ive found. anyone have any idea on how i can find higher octane gas in lubbock, tx?

Did you try using google.com? I just searched and there's a lot of people talking about specific stations there that have different grades of fuel..