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Discussion Starter #1
My car '02 2.5RS has always backfired a little. At least since I put on the Ganzflo. Now that I have installed the Brullen Catback It is very noticeable. Is it a fuel/air mixture thing and would a Chip or something help. I did the ECU reset thing about 4 days ago. Could the ECU be confused because the car sees 3 different driving styles(w/wife in car, w/o wife, and my 16yr. old's).

Second dumb question. Since I have done a few mods should I consider a high octane fuel? I know the higher the octane the slower the burn, but I should be pushing more air thru the engine now and wondered if it would make a difference.

Thanks
 

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2001 ImprezaRS2.5 Coupe White
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1,513 Posts
Good Question....


I have a 2001 RS and I did not notice a back fire until I put on my Brullen Cat back exhaust. Mine back fires when I let off the gas after reving above 4000 RPMs. I would also like to know if this is normal.....

:confused:
 

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Scoobymods Guy
2010 Legacy 3.6R Limited
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someone correct me if I'm mistaken but the backfire is normal, it's unburnt fuel hitting your cat converter. It's louder now because the exhaust lets you hear it. And no you shouldn't go to a higher octane than it says to use because your car's software isn't programmed to take advantage of it. It would be a waste of money. If your car is pinging that is another story, then go up one grade and see if that helps.
 

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Discussion Starter #4
I'M YELLING AT MYSELF.....DO A SEARCH!!!!!! Sorry but I had to do that. I did a search and found that it is kind of normal. There are several threads about it. Sorry
 

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Hey Cone Eater,
No worries mate! :sunny: It's all good. To make you feel even better, I've noticed considerably more back fire after the Cobb CAI was installed. Of course I find myself driving a lot harder. I need to slow down, that Cobb CAI is dangerous. Last thing I need is more tickets.

-JOE
 

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'00 2.5RS SRP '04 4STR-XT OBP
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My my00 backfired a lot when I first got it...I moved up tp 91 octane...helped somewhat....added a custom 3" CAI...helped even more....started using 2 to 4 oz of Marvel Mystery Oil per tank....so far no back fires for over two months! My back pocket dyno also says I have a quite noticable gain in low end torque and over all Hp! Milage around town has dropped to 19 mpg (from 20) but out on the road it has gone up to 26 (from 22)!



:sunny:
 
H

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Marvel Mystery oil? Isn't that just kerosene?

My car backfires like a '58 Microbus.

And I use '92 because the sulfur content seems to be less. Or something. It doesn't stink as much anyway.
 

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'00 2.5RS SRP '04 4STR-XT OBP
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MMO is not 'just kerosene' as some (idiots..... but not on this thread!) might suggest! It is an excellent top end lubricant as well as a combustion chamber cleaner, fuel pump lubricant, fuel injector cleaner and antiknock compound! Sure it may look funny....but you can't beat what it does unless you are formulating your own fuel from specific refined petroleum distilates!

:sunny:
 

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Discussion Starter #9
I was just thinking...

If my car is going to backfire, which I'm getting used to, I wish I could get it to do it like my old(63) VW Bug. I could turn the key off while going down the road, leave the clutch out and turn the key back on. The resulting backfire would produce a nice 1' flame or so coming out the exhaust. :D
 
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Hmm. You'll want to kill the spark but keep the injectors going..

Could possibly be done with a simple switch. :)
 

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2001 RS Blue ridge Pearl
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The popping is normal, thanks to the boxer engine. I like it. =)

I tried mid-octane fuel for a while, detected absolutely no difference in performance or exhaust 'dirtiness', so now I'm back at 87.
 

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2000 obs green
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I cannot be certain on this but by the sounds you all are running some sort of aftermarket exhaust system, have any of you really checked to see if all of your connections are truly air tight?


Posted from Rs25.com App for Android
 

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05 STi WannaBE
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Holy 11 year old thread bump batman!
 

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2002 RS, Blue Rust Pearl.
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Hello fellow bugeye, I thought backfire was the shit??

With an exhaust/intake, and our cars already running like pigs stock, It's bound to happen, and it won't hurt anything, just scare the shit out of whomever rides your ass haha.
 
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