Doobiewah

An acquaintance knows a petroleum engineer with Shell. He (the engineer) said that although Shell is a top tier fuel, their premium (V-power) has several more additives than the regular and mid-grade (same with other majors, like Chevron, etc) and for those additives, alone, he would run premium in our RDX's as it will keep the engine performing at peak. Makes sense to me, considering what we pay for these vehicles....., so I think I'll just run the premium. Not worth it to save a few bucks. I think it's a peace of mind thing, too. I have no skin in this game, though, and understand that it is a personal preference.

JMHO.

xyzbill

I have read this before - it use to be totally true - Google Tiger in the Tank TV add -

I can't recall the last time I saw an ad that claimed premium had more additives to keep your car engine clean - you would think if it was really still true that the gas companies would market it.



I have ran cheap gas in many cars - not top tier - and never had a problem -

Upgrading to Top Tier gives you the additive package that will keep your engine clean - even with lower octane.

I am more curious about it that trying to save a few $ - I keep wondering if the RDX engine is really just the exact same engine - tunes the same - as what is used in the Honda Accord - and that they RECOMMEND premium to make the owner feel special.

Doobiewah

So, my comments noted above basically run us full circle. Again, until I can really confirm anything else, I will continue to run the top-tier premium as I know I can't hurt the engine at all. Anecdotally, I might hurt it if I run top-tier regular. If I could confirm that the engine and tuning are the same in the Honda and the Acura and, as we know, Honda does not recommend premium in theirs, I would consider downgrading the fuel. Not sure if that's possible and, again, it is a matter or personal preference. I do recall my sales person telling me that the dealer ONLY ran premium in the RDX and that is the recommendation of their mechanics. I don't know that anyone is right or wrong in the decision that they might make. I haven't read anywhere that someone's engine tanked because they ran regular (like I have read about some who ruined their Harley engine running regular). I read Consumer Reports study. I've listened to a petroleum engineer. All any of us can do is make a personal decision. I'm not one of those forum participants who looks to deride others if their choice is different from mine...I join and post to learn.

dirleton

I would not be surprised if the average dealer filled their RDXs up with regular prior to delivery. Not surprised at all.

thoiboi

Got any other conspiracy theories to share?

dirleton

No conspiracy. Just squeezing profit.

thoiboi

That's why prior to delivery, i GO with the tech to the gas station (Shell V-power or bust) to make sure they press the 91/93 button


Also i steal all the mints off the finance guy's desk.

Doobiewah

I was lucky since the finance guy had just stocked up with nice Halloweeen candy!!!

Gadgetjq

It won't end the debate but it's an interesting read: Why You Might Not Actually Need Premium Gas - Consumer Reports

DerHossMeister

Yes, it is about the tuning of the engine and preventing pinging or detonation. It's also about the emissions the engine generates with a given tune. CAFE standards and emissions regulations are driving the auto industry anymore.

snorf

My younger brother's Toyota Tacoma pickup (4 cyl) had 292,000 miles on it and he never used anything other than off-brand, cheap gas. He never had a fuel-related issue. Fifth gear synchronizer went out and it would cost more to fix the transmission than the truck was worth. He sold the truck and the guy took the engine out to use in another vehicle. The new engine owner is now using it and uses off-brand cheap gas. Does top tier gas make a difference? Perhaps. Will your engine last without it? I believe so.

Majofo

thoiboi

Majofo

I think what snorf is saying, remove piece of shit Honda engine, replace with Toyota Tacoma engine. Problem solved.

snorf

What snorf is saying is that regardless of the type of gasoline used in an engine the engine will last. BTW Majofo, that pic you posted looks a lot like my brother. If you put some hospital scrubs on the pic it'd be a dead (not a doctor joke) ringer.

Majofo

cu2wagon

Yeah, but in full disclosure... Toyota pretty much designed that Taco engine to run on chocolate milk.

It's pretty over designed and under stressed.

justnspace

iTrader: (1)

Did Snorf really refer to himself in the third person?
Justnspace seems to think so!

Majofo

Oh, I thought he was just snorfing

loved my old acura

I have a 2016 IX A spec the dealer told me to use Shell only PLUS the manual states to use premium but the dealer said they put Plus 89 in all the cars. my question is my DCT is a dog and I tried to sell it back to the dealer I think it's a true lemon well I still have it and not happy with the car. so since it runs like crap anyway will Shell regular be ok to use? I have always used shell gas in all my cars never cheap gas. I would not mind spending the extra money on the gas but I dont think this car is worth it.

viperkorn

I am new here but I read some of the early post about cost per year and well not that much of a cost to put in what you are supposed to put in. You say the car "runs like crap anyways" but it runs do you want to risk it running worse? I think the dealer putting cheaper grade gas was just a way for them to save money They put gas on multiple vehicles where you only fill yours. Just my opinion.

Majofo

Acuras are pieces of shit undeserved of premium fuels

Majofo

You'll just look like an asshole putting premium in it when your Honda counterparts are putting regular

horseshoez

iTrader: (2)

Guess I'm an asshole then.

Majofo

No one contested that..

Okay being serious.. love octane threads almost as much as I love oil threads.

Use whatever octane or brand you want, just don't whine about it
or try to flash your master tech certificate from the internet here..

horseshoez

iTrader: (2)

...and don't complain when you run Regular in a car designed for Premium and you end up with poor performance and/or engine damage.

Majofo

Seriously though, there are a few instances where the same engine (we're talking same J series with the same heads) are recommended Premium for the Acura brand and Regular for the Honda brand. I just gave up.. just like Honda / Acura gave up years ago.

Truthfully, unless it's a bad tank of gas or a couple of bad fill-ups. Octane issues won't manifest until many miles down the road.. usually it's someone else's problem by then. Especially with some of the internet experts here giving advice on a leased vehicle. Usually the first manifestation is clogged cats. I can attest that 200k miles on the X (I just changed the wideband o2 sensors on her), that the monoliths are clear (only fed premium her whole life). It did need a valve adjustment around 150k, but it ran rich only for a couple weeks before I adjusted the valves (tight exhaust valves).

jcross1231

I still don't understand this issue of buying an Acura and then cheaping out on gas.

horseshoez

iTrader: (2)

In the case of same-same-same, Acura vs. Honda I see the argument; as far as I know, the J32A3 engine in my 3G TL never made it into a Honda, so a case for using anything other than Premium cannot be made. To take it a step further, to the best of my knowledge, no J32Ax engine was ever put into a North American Honda model, so the North American J32s, et-al, require Premium.

Did I miss anything?

Majofo

The +15 TLX has the J35Y6
So does the +16 Honda Pilot

TLX manual says +91 Octane
Pilot manual says +87 Octane

The TLX has +10 hp and +5 tq
It's bc it's adjusting timing for the lower octane
and throwing unburnt fuel onto the cats
losing power, fuel efficiency, and possibly damaging the cats and engine

Gadgetjq

Adding to a gas thread, YAY! Ok, not so much but Jalopnik has posted a fuel related article related to money saved by using regular over premium....or not. Interesting reading.

Here's the link.

Unfortunately the article doesn't solve the premium fuel "recommended" vs "required" question.

Cheers!

Majofo

That's a lot better article than most of the bullshit that's been written by others.. It's like I said.. it's a downward slope. You probably won't notice ill effects early, but the unburnt gas being spit down the pipe and the knock all have an effect. A knock sensor pulls timing when?!?!?!?!?!? the engine experiences knock.. very good class. Knock can damage ringlands, head gasket, piston / head surfaces. Knock can also shock the rod bearings and lead to premature bearing failure. All of this is tear down shit.

Pulling timing throws unburnt fuel down the pipe which can ignite in the cats and lead to breakage in the monoliths.. this is a domino effect.. any disturbance in the flow of the cat becomes a hot spot which leads to more damage in that area and can eventually clog the cat. This can foul your wideband a/f and o2 sensors, create excessive backpressure which can be damanging and cause rough idle / stalling. It'll definitely drop your fuel efficiency. Cats aren't cheap either. All that being said.. it's not worth the few bucks.. unless you're leasing it and don't give a damn about it.. or the planet.

Coolwater

I have about 1000 miles on the rdx with 87 octane. Dealership that sold me my rdx pretty much told me regular is fine. I tried premium for 1 tank just to see if there was any difference. Power was the same and mileage was about the same too. My salesman drives a tlx and uses regular from Costco. No problem at all.

-cW

Majofo

Octane threads..

hongthan

I just did a one-day trip yesterday from Little, AR to Nashville, TN. It was about 750miles. It averaged around 24.5 at 75-80mph speed. I filled it with premium plus 93 at Sam's club before the trip, then added premium 89 on the road. I did not feel any difference in terms of power. Anyway, love the ACC, LKAS and cooling seat in Advance. It made my summer long day travel more comfortable than before.

justnspace

iTrader: (1)

octane threads.....

losiglow

iTrader: (1)

I think I lost a few IQ points just reading the last page of this thread.

Average price difference between regular and premium = 25¢

10K miles per year @ 25mpg = 400 Gallons, x 25¢ = $100 per year difference
15K miles per year @ 25mpg = 600 Gallons, x 25¢ = $150 per year difference

$10000 - $30000 car. Arguing over spending an extra $100-$150 per year? Dafuq?

Seriously, if there even a remote chance, even 10%, that premium is better in any way (performance, engine longevity, fuel mileage, makes the paint last longer, ass feels better on long trips), there's really no good reason not to use it. This is the exact reason arguing over synthetic vs. conventional oil is DAF. You're looking at about $50 a year difference (if you do it yourself) for the chance it would be better. I'll take that chance.

cu2wagon

Easy way to tell what octane to use. Go to this link and see if your car marque is listed:
https://www.edmunds.com/luxury/

If yes, use premium. If no, use, I don't know, whatever the hell poor people use.

Majofo

Kia and Hyundai



/thread

Tech

Looking at both the Honda Canada and Acura Canada sites, the specifications for the engine are 100% identical for a 2017 Accord Coupe V6 Auto and 2017 Acura RDX V6 Auto.

Recommended fuel:
Accord - Regular
RDX - Premium

Go figure!

My neighbour with a 2003 Acura TL S (V6 6 speed) has run over 200,000 kilometers on nothing but regular.