V-Power gas vs. regular

[luvmy94q]

An engineer friend of mine who drives a newer Q said he puts regular gas in and the computer adjusted -- sounds like B.S. to me but w/ the prices skyrocketing, any feedback w/b appreciated.... Anything but V-power in mine and I can IMMEDIATELY tell the difference...

[luvmy94q]

P.S. I have NEVER put anything but premium in, but the cheaper stations,

[maxnix]

Cheaper stations don't have the detergents. Always use Tier 1 Premium from a station with new tanks and high volume.

BG44K before every oil change never hurt.

[MinisterofDOOM]

An engineer friend of mine who drives a newer Q said he puts regular gas in and the computer adjusted -- sounds like B.S. to me but w/

Your friend is correct. All (or very nearly all) modern engines (and indeed most engines made in the last 15 years) including the new Q's VK45 will compensate for lower-octane fuels. That's why you usually see "RECOMMENDED" instead of "REQUIRED" when referring to use of top-grade fuel on newer cars.

Still, I'm another believer in only putting top-grade, top-tier fuels into my cars.

[qship96]

Premium unleaded only for a properly operating q45

HOWEVER, for many {most?} q45 owners, who are showing a knock sensor code stored in memory- might be perfectly fine to use regular grade unleaded, as your ECU is operating in safe mode with the timing already retarded - using premium may just be flushing dollars down the drain, as your engine is not operating with timing map advanced to need or benefit from it.

[Haitian_King]

Premium unleaded only for a properly operating q45

HOWEVER, for many {most?} q45 owners, who are showing a knock sensor code stored in memory- might be perfectly fine to use regular grade unleaded, as your ECU is operating in safe mode with the timing already retarded - using premium may just be flushing dollars down the drain, as your engine is not operating with timing map advanced to need or benefit from it.

Yes. Quite true. It may be a coincidence, but when I first got my Q, (I was dumb as hell boy.) I spent the first three months putting in Regular 87 because I was of the "All gas is the same."

Then I developed a nasty rough idle and I began to tear my hair out fussing about the MAF. Turned out it was the #8 injector. After I got it replaced, I never again put anything less than 91 in my Q.

I've been trying to convince my madre to start using Premium in the MDX but she's reluctant. She just loves her Regular. The car still runs very well, but I'm anxious about the potential damage it may be causing. I'm considering running a can or two of BG 44K for the peace of mind.

[seldomseen]

If I'm down to a half tank of gas I will fill up tank up using Mid-Grade, but when I'm down to 1/4 tank or less I just fill it up with Premium. Never had a problem doing this yet. I won't touch the Regular unleaded though...

[Haitian_King]

If I'm down to a half tank of gas I will fill up tank up using Mid-Grade, but when I'm down to 1/4 tank or less I just fill it up with Premium. Never had a problem doing this yet. I won't touch the Regular unleaded though...

I have some sort of weird personality quirk that stops me from being at the gas station and not filling up.

Just the other day (Even I thought it was weird.) I had a little above 3/4's of a tank and I still topped up with 92 Octane @ $3.25/gallon.

I must be crazy.

[Adeianos]

I'd love to get premium at $3.25/gallon, I'm sucking it down at $3.99

[lino]

I pay $4.85 Canadian for the equivalent of a US gallon which translates in $4.75 US.

[IceCubeFoSho]

I only put in V-Power gas in my vehicle. I'm not too sure if its that much better than other premiums, but the one by my school is competitively priced with the other stations around the area (sometimes the V-power is cheaper than their premium!)

[StarPD]

Using less than "Premium" in a correctly operating Q will retard timing, resulting in less power and lower fuel mileage. The reduction in fuel mileage offsets the saving in fuel price, so you get a car that doesn't perform as well, yet costs the same to run.

In other words, it's not only false economy, but counterproductive.Don't do it.

[qship96]

Up until just a couple of years ago, I used only 94 octane Sunoco in the Q-for some reason, they stopped selling it in the Balt/Wash area- does anyone here have it in their area?

[Skibane]

The engine was designed to run on Premium. When it's running on Mid- or Regular-grade, the timing is retarded in order to avoid pre-ignition (pinging). The engine computer may "learn" to run in this manner, but it's still running with retarded timing.

Generally, an engine makes the most power when the timing is advanced to the point just below pre-ignition. Retarding the timing reduces the power output. Note that this doesn't just occur when the engine is under a heavy load - If you've ever adjusted the timing on an engine while it's idling, you already know that the idle speed decreases and becomes less smooth as you retard the timing.

Less fuel octane = more timing retard = less power = more throttle required to produce the same amount of power = higher fuel consumption = little or no cost savings by using Mid- or Regular-grade gas.

BTW, Shell claims that only their Premium (V-Power) grade has the ability to dissolve existing deposits, while their Regular- and Mid-grades only help keep deposits from forming. The implication is that there are more cleaning additives in their V-Power grade than in the others.

[SynisterQ]

Up until just a couple of years ago, I used only 94 octane Sunoco in the Q-for some reason, they stopped selling it in the Balt/Wash area- does anyone here have it in their area?

I'm sure Haitian King can vouche for me, but I was in New Jersey back in 2002 and all the gas stations had 94 octane. I thought that was awesome.

[jimbyjimb]

Always run manufacturer reccomended octane. The computer is set to time the engine according to the octane. The higher the octane, the slower the burn, the longer the burn, so it creates power longer. This effects how you would time the engine. On the old gals it's a simple matter of twisting the distributor the right way to retard the timing. On these newer gals you'd have to reprogram the ECU, which cost-wise would be of no value. There is no practicality in paying big bucks to have the performance taken away from your full-sized luxo-performance V-8 powered land yacht. In theory you may be able to retard the timing enough via the cam sensors to run a lower octane fuel, but that's something you shouldn't mess with unless you know what yer doin! I might consider retarding the sensors fully and using mid-grade, but I think the better half in me that likes going 140 on the expressway late at night will win that battle. In essence, probably just best to leave her be.

[luvmy94q]

Thanks for all the feedback -- like jimbyjimb said, I will leave my "full-sized luxo-performance V-8 powered land yacht" ALONE!! I, too, enjoy those 140 mph late night cruises... These cars are expensive to maintain but worth every penny (or $3.73/gallon) if you want them to run at top performance -- Q's are AWESOME...

[ScottJackson]

I use cheap 87 octane when I just want to cruise for long distance. The engine doesn't need high octane at low throttle angles. It can use full timing and low octane for just cruising along. Yes, when I put the pedal down with the 87, there's less power than with premium (knock sensors retard the timing, and mine is advanced 3* above stock). But fuel mileage just cruising down the road is the same with 87 as with 91.

[Jesda]

According to Dennis, the Q's ECU memory is so brief that it doesn't ever really learn to adjust to lower octane fuel, so you get possible detonation each time you start before it retards timing.

Premium unleaded only.

[Q45tech]

Remember the PREMIUM GRADE of 1987-88-89 is very different from what the marketing department calls Premium today.

Sure todays octane measured at refinery may be close on the day it was made, but octane longevity may be another matter.

Some how technology advances have allowed a 7-9% increase in volume produced from each barrel inputed. This has been at the expense of BTU per gallon which has steady decreaed so the PREMIUM of today generates less peak power, compression pressure and gets fewer mileas per gallon.AND ALL THIS IS BEFORE ETHANOL is even added.

http://www.rockettbrand.com/te...e.pdf

Why does diesel cost more because it can produce 139-140,000 BTU vs gasoline 125>114>110.000 BTU per gallon.

[maxnix]

Why does diesel cost more because it can produce 139-140,000 BTU vs gasoline 125>114>110.000 BTU per gallon.

Quite simply, the rest of the world primarily runs on diesel. Trucks, cars, power plants, boats, tractors, etc.

Therefore gasoline is relatively cheaper because of less demand from expanding 3rd world countries who are primarily building infrstructure.

Also, US requires extremely low sulphur now, so refining and sourcing of crude costs are higher for US.

[jimbyjimb]

Probably the best thing that a human could do for the world at this point is to buy a diesel and brew your own biodiesel. Big savings for the wallet and for the atmosphere. I saw an episode of trucks where they actually were able to make more HP and TQ on their own special brew of biodiesel that they estimated cost them 77 cents a gallon. It took one-weeks brew time approximately for 25 gallons. When I worked for Swift in 2005 and diesel prices were around the area of 2.80 to 3.00 a gallon Swift sold diesel, at a profit, to owner/operators at 1.25 a gallon. People think buying hybrids save the world. Diesel engines are amazing. What with diesel technology catching up to that of gasoline. And they last so much longer. Time for an International V-8 swap into the Q? That'd be pretty darn cool.

Forgot to add in to check out the world's coolest super-sports car. The Audi R8 concept is powered by a Diesel engine. Check out Gale Banks' endeavors as well.

Modified by jimbyjimb at 6:18 PM 4/13/2008
Modified by jimbyjimb at 6:20 PM 4/13/2008

[Haitian_King]

Probably the best thing that a human could do for the world at this point is to buy a diesel and brew your own biodiesel. Big savings for the wallet and for the atmosphere. I saw an episode of trucks where they actually were able to make more HP and TQ on their own special brew of biodiesel that they estimated cost them 77 cents a gallon. It took one-weeks brew time approximately for 25 gallons. When I worked for Swift in 2005 and diesel prices were around the area of 2.80 to 3.00 a gallon Swift sold diesel, at a profit, to owner/operators at 1.25 a gallon. People think buying hybrids save the world. Diesel engines are amazing. What with diesel technology catching up to that of gasoline. And they last so much longer. Time for an International V-8 swap into the Q? That'd be pretty darn cool.

Forgot to add in to check out the world's coolest super-sports car. The Audi R8 concept is powered by a Diesel engine. Check out Gale Banks' endeavors as well.

Modified by jimbyjimb at 6:18 PM 4/13/2008

Are there "quiet" diesel engines? I'd hate for my Q to sound like one of those big clattering Dodge Cummins Diesel pickups.

Modified by jimbyjimb at 6:20 PM 4/13/2008

[Kiven422]

You guys have all this talk but the Q was made in 1990. Today the only "premium" available is a 91 octane rating, on top of that 10% of its ETHANOL.

My smog guy was telling me I could probably get away with 89 Octane (midgrade/unleaded plus). I've never put anything but premium, but with prices as high as $4.19 in my area (how high is it gonna get in the summer?) I think I just might give it a try or retire the 94Q its a damn guzzler. The 93 ain't so bad.

I'm looking at the new Civic SI 4 door or a 03/04 Infinti M45 --- those are bad, but it dont give you that japanese muscle car feel like the Q.

[MinisterofDOOM]

Actually, diesel is expensive in the US due to the primary refining method we use here (a particular form of cracking). We produce significantly more gasoline than diesel in the process, which is responsible for our "backward" (from the viewpoint of much of the rest of the world) scenario where gasoline is cheaper than diesel.Of course, the reason for the choice in refining method is due to demand. And the way diesel cars (or even the idea of diesel cars) are treated in the US is at least partly responsible for keeping that demand situation from changing.We have a situation where the last diesel cars most people remember were heaps of poorly engineered unreliable, noisy, smelly garbage (thank you Oldsmobile). Couple all that with the ridiculous price differences between diesel and gas versions of any car, and most Americans just don't have the jones for a diesel car.If we could educate the populace, things might change, but it'll take a lot of education to compensate for so many well-engrained misconceptions.

Fuel prices have never been about energy/cost. If that was the case, things would be much different, not only here, but across the world.

If only the morons marketing Hybrid programs would devote their efforts to real viable options like diesel, we'd be much better off. At least diesels actually yield benefits during normal US driving conditions. I'd like to see a hybrid powertrain improve my 75 mph cruising fuel efficiency.

Er...Sorry for the tangent...

[Haitian_King]

You guys have all this talk but the Q was made in 1990. Today the only "premium" available is a 91 octane rating, on top of that 10% of its ETHANOL.

My smog guy was telling me I could probably get away with 89 Octane (midgrade/unleaded plus). I've never put anything but premium, but with prices as high as $4.19 in my area (how high is it gonna get in the summer?) I think I just might give it a try or retire the 94Q its a damn guzzler. The 93 ain't so bad.

I'm looking at the new Civic SI 4 door or a 03/04 Infinti M45 --- those are bad, but it dont give you that japanese muscle car feel like the Q.

I get 92 in my Q all the time.

[NightRiderQ45]

or a 03/04 Infinti M45 --- those are bad, but it dont give you that japanese muscle car feel like the Q.

Ummmm, the 03/04 M45 has more muscle than your Q, plus it's a better car.

[qship96]

Ummmm, the 03/04 M45 has more muscle than your Q, plus it's a better car.

Faster,yes.....a better car? No, not even close in engineering and build quality. Almost flimsy compared to the overbuilt g50......and you have to stare at that butt ugly mini-van looking dash every mile you drive it.

[maxnix]

You guys have all this talk but the Q was made in 1990. Today the only "premium" available is a 91 octane rating, on top of that 10% of its ETHANOL..

Only if you are a captive of The People's Republic of Kalifornia.!

[NightRiderQ45]

Yeah, I don't know how they are built, I was speaking of performance. I've heard many issues with that car, maybe that's why they changed up the design after 2 years.