SI with 87 octane gas *Threads merged*

[bluek20z3]

i sick of seeing this and the idiots who think putting 87 is ok........Have you guys noticed on the fuel door it say "Please use premium fuel only" I mean what part of that don't you understand. people are so cheap, the difference between filling your car up with 93 and 87 is prob. like $2.00.....So to save yourselfs 2 whole freakihng dollars you would rather risk destorying your engine all because i "I can't afford the extra 2 bucks so i'll throw in 87" it only takes one pre igition cycle to destory your engine just one, not to mention if you do end up destorying your engine because the knock levels are throw the roof guess what VOIDED WARRNETY from the dealer if they test your fuel and realized you used 87, and you will be stuck with a 4000 bill for a new engine all because you decide to fill up your si with 87 2 or 3 times or more because you were like "wow it runs slower on 87 but it still gets me to point and be B i guess i use it every once in awhile" so you can save a grand total of 5.00 because you filled up with 87 3 or 4 times.If your to cheap to put in 93 trade your SI in and buy a R18 or a hybird.

Sorry for sounding like a jerk but if you want performacne it dose cost some moeny.

[atallah24]

im sure its just like 5-8 bucks for a small bottle. (put in with full tank..)

its pretty much the same as gas treatment but for injectors....u should do it every now and then

[badassdawg]

I bought a used 07 si. I don't know which gas the previous owner used(older guy) but my engine does make a knocking sound, If i start using 94 now will it eventually reverse the problem?

[EchoHawk7]

no if it knocks or tics its usually a timing problem and youll have you get it re adjusted at a shop, there is a distinct knocking though from engine problems and the vtec rocker inside the engine. ( vtec works off oil pressure so when you engine gets hot the vtec mech. wants to kick over and thats what your hearing)So have someone else listen to it. Mine Tics/knocks too after i run it hard or for a long time but thats normal engine operation at those temps. Ive never put anything less than 91 in ever and i really dont run my car that hard I only take her to red line in 2nd and 3rd if im feeling giddy on on ramps. thats all we get in AZ, sometimes 93. i miss my NY 94.

oh and for everyone with a counter of..."what about the computed timing control?". Thats fine and all but its not a cure all to timing issues it just helps to reduce major problems that were possible in engines without it.

[ryker]

Knocking or pining sound under load - ie take off or up a hill. This is from cheap gas. pinging - google it.

[EchoHawk7]

Originally Posted by badassdawg

I bought a used 07 si. I don't know which gas the previous owner used(older guy) but my engine does make a knocking sound, If i start using 94 now will it eventually reverse the problem?

is it under load? cuz then ryker is right but if its just sitting there and it sounds really shitty then take it to a dealer.

[OrdnanceMarine]

While I can't verify what kind of sound you're hearing, the #1 underhood sound that falsely gets people worried is actually just the fuel injectors tapping away. All four I4Hondas I've owned do this.

[FALer]

Originally Posted by kenny rogers

Actually, I was just talking to someone about higher (and therefore colder) elevations such as Colorado... I was told they actually sell less octane gas (85 instead of 87 as "regular). However, that has more to do with the altitude and not the tempurature.

Keep premium in it, you just get more horsepower out of colder air

Higher elevation = less oxygen. You don't need the same octane as you do where there's more oxygen. I'd still be careful with a FI car, however, since you're cramming more oxygen into the cylinder with each intake charge.

[zetarin71]

shell v-power 91octain=500horses

[Ghetto2315]

Seafoam is excellent stuff. I swear by it

[zhunterzz]

93 Octane since I got it, now I can just about fill up with $22

[MaddMatt]

Has anyone looked to see what the owners manual specifically says? Anyone? I have. 87 octane is fine, as long as you don't mind not making 197hp. The only thing the manual say specifically regarding lower octane is that running less than 87 octane may result in engine damage.

That tells me that 87 octane will not damage the engine. Will you make 197 hp? No. But you won't be replacing the engine either.

[djphoenix18]

^ Go ahead and give it a shot.

I dont understand why people bought the car if they cant even afford premium gas.

If money was an issue to them, they should have bought a DX

[OrdnanceMarine]

Keep in mind Honda just needs the engine to last 36,000 miles and then you're on the hook for repairs. The Owners Manual states that, "Use of a lower octane gasoline can cause occasional metallic knocking noises in the engine and will result in decreased engine performance." I can't imagine "occasional metallic knocking noises" are the path to engine longevity, even though the engine may still last way past warranty.

[EchoHawk7]

Originally Posted by OrdnanceMarine

Keep in mind Honda just needs the engine to last 36,000 miles and then you're on the hook for repairs. The Owners Manual states that, "Use of a lower octane gasoline can cause occasional metallic knocking noises in the engine and will result in decreased engine performance." I can't imagine "occasional metallic knocking noises" are the path to engine longevity, even though the engine may still last way past warranty.

honestly the above post too! its amazing (even though it shouldnt be) how many cheap people are out there, or maybe they are just too dumb to realize what they were buying. They obviously got had by the dealer when they were upsold. Good job on getting screwed guys.

[MaddMatt]

^ Go ahead and give it a shot.

I have. Several times. At least 3-4 times last fall when there was no gas to be had in the southeast except 87 octane (if you could even find that), and once more when I just flat brain-farted a few weeks ago and put 87 in. At no point did I hear any knocking, and the car runs like a champ. And fuel mileage was completely unaffected.

Amazing....

Too many posts here make it sound like you've destroyed the engine by running it just 1 mile on 87 octane. Nothing could be further from the truth.

[bossman]

You may not be able to tell if 89 or lower octane was used on this car but if the previous owner put it in and ran the car hard you'd be able to tell by the plugs.They could be melted,busted,or otherwise not normal.Sparkplugs will tell alot about how a car was treated and ran.

[bluek20z3]

if your car ever requires any kind of warranty claim for what ever motor problem my ocuur and honda realizes that u used 87 they may void your warranty........dealerships are screwed up like that even by law from the EPA from 95 to now no matter what car you drive ( vette, m3,turbo evo, sti, mini van, truck)the car should still be able to ran 87 no matter what.Are cars can ran 87 but you increase the chances of developing engine problems alot sooner or something to go wrong allot easier. Bottom line if you look at the inside of your fuel door it says preunim fuel only.............personally i always put 93 in my car......i even tried 100 oct and belive or not the car ran real smooooottttthhhh i wish we had 100oct at the pumps it would make tuning cars alot easier lololol

[bossman]

I personally don't se a HUGE problem with using low octane fuel,after all,octane rating just lets the consumer know how knock resistant the fuel is as tested on a test engine under controlled conditions.I don't think the engine is under alot of load if you gently cruise around town and don't try to accelerate hard or use your high gears to climb hills.Alot of the techniques(SP?) that people use to save fuel are useful for keeping load on the engine down and if you could do it all the time then you could "theoretically" run lower than reccommended octane fuel.

[MaddMatt]

they may void your warranty

I don't see how when the owners manual does NOT specifically say to avoid 87 octane, and does NOT state that the use of 87 octane will cause any damage. It only specifically states to not use anything LESS than 87 octane. It also states to not use any gas with MMT addative.

Now, if you put in some 85 octane like they have in places in the northeast, they may have a point....