A lot of new vehicles are requiring Premium fuel. At $2.20 and up per gallon, will these new vehicles run OK on regular?

 

Probably not efficiently.

 

True...I'm sure they'll be okay but you won't get the advertised power ratings out them.

Motor Trend did a test on cars the recommended 91 or higher and ran them on 87 through their series of performance tests. The performance gains are around 5-10% using the premium versus regular.

 

The computer should recognize it and adjust apppropriatly. It should be 100% safe unless its like an exotic like a ferrari or something.

 

should be ok if you drive normal, might help to run some techron or something like that everyonce in a while. i put regular twice in my car that required premium and it used up a lot of gas quickly. where are you at? im paying 2.40 for regular.

 

I was told to go with large brand fuel stations which have fuel injection cleaners. Maybe if your towing up hills use the 91 to get alittle more power. just my 2 cents

 

It depends alot on the compression rating, if it requires high octane because it is a high compression engine (which some newer engines are to get the HP they have them at), running regular could cause detonation that you may or may not hear. Detonation will hurt or destroy these engines in time. If they say premium, it isent worth the chance of destroying your engine.

 

I've run super premium (94 is the best we get in Canada) for years in my motorcycles for that very reason -- high compression engines. I hadn't heard of premium being recommended for 4-wheelers. What kind of vehicles are we talking about here? Import cars or Ford trucks? In recent years my bikes have always been upwards of 11:1 so using premium seemed like a pretty good idea. How high are these new 4-wheelers really at?

 

The 5.4 and 4.6 are almost 9:1, and some of the "hi performance" motors can run as high as 11:1. The Caddy Northstar (early ones) required 93 octane.

 

I'm impressed! I honestly didn't realize the car/truck manufacturers were catching up! Thanks for the info.

 

The supercharger on my buddies T-bird started goin bad (back in the day). They tested his fuel.....all he ran was 87, required no less than 91.
They didnt blame it on the gas....but they said it didnt help.
So, yea, if they say a higher octane is needed...listen.

 

my friends boss only runs regular in his cars. a jaguar xk and in his mercedes sl.. dont know what he puts in his new bentley gt but he leases everything.

 

I run my car on 98 (that is premium in Australia), 91 is standard, and 95 is also available.

It will depend if your car has knock sensors, and whether you like the sound of pinging or not...
If your engine is designed to run on premium, and you run on regular, what it will do is the engine will start pinging - pre igniting the fuel, it should not cause any damage to modern cars, but in older cars with high compression, it may destroy the surface of your piston head and valves.
The knock sensor will detect this "pinging" - depending on how sensitive it is set - and retard the ignition timing of the engine.
This will cause a drop in power of approx 10% or so - again depending on how the car is set up, some will retard up to 25%!!! - and because of this drop in power, fuel economy also gets worse.
I know with my car it is worth paying the extra 10% more for 98 over 91, because I get approx 15-20% worse fuel economy, not to mention the power drop. It has also enabled me to "desensitize" the knock sensor, as I know I will be putting 98 in it all the time, if by chance the engine "pings" a little when it gets hot, it will not retard the ignition timing at all, therefore more power for me

Anyhow, hope that answers some of your questions...

 

I started to get some knock in my '96 TC (with the 4.6) using 87, so I switched to 89. That helped for awhile, but the knock came back, so I went to 91. When THAT no longer helped, I mentioned it to one of our service advisors. Before I even finished the sentence, he stopped me and said: "you need a new mass airflow sensor." Replaced it and she now runs perfect on 87, and my mileage is the best it's ever been (avg. 23-24). Moral of the story: if it's designed to run on 87 and it's knocking, it may be more than just the grade of fuel.

 

If you hear the pinging and it is there when you are under load and doesnt go away, then it can and will damage modern cars, pre ignition is pre ignition. The knock sensor should eliminate it immediatly if your using the proper octane fuel. Go with the mfgs recommended octane requirments to keep from having to buy yourself a new engine.