I put 4 dollars of regular in my car when the nearest station was out of premium. Didn't feel a difference there. I also filled 1/2 of my tank with regular before I realized that it was regular, no overwhelming difference there. I noticed slightly less performance, but that was probably psychological. All in all - no real loss in using premium, so better to be safe than sorry.

 

Maybe most folks who lease will use regular unleaded. It woun't hurt your car, just lower performance and a few pings and knocks. I read on another forum (Acura and Lexus something?) that it will not harm your car (he used reg unlead for 3 years, but manufact. says to use prem unlead). The ECU is programmed to work under both reg unlead and prem unlead.

So my question is... is this really OK???

 

My dealer told me that regular unleaded is fine for the coupe. I have used regular unleaded from the start with no problems.

 

Hmmm...very interesting.

 

I'm sceptical about using anything other than what the Nissan recommends. If nothing else, the lower octane fuels will curtail performance and mileage by detuning the engine, and may be harmful if pinging or detonation is encountered.
In the Coupe they recommend premium (at least 91 Octane) and in the A/T Sedan they recommend premium, but 87 can be used in a pinch.
The higher hp (6M/T) Sedans of late also require high octane.
I wouldn't deviate from that.
My .02
C.

 

I get about 400 miles to the tank on 87 octane =)

 

where's the luv for your cars? 87 octane...sheesh.

 

You missed at least one. Ther highest octaine gas typically has the best detergents for that brand. Shell V Power, for example, is only offered in their 93 octaine gas. Some cheapo gasolines have virtually no detergents. As the old commercial use to say: pay me now or pay me later. Valve jobs ain't cheap.

 

buy a toyota prius gotta love 80 BHP my brother drives one and it gets 45 mpg on 87 octane

 

It's prolly ok to use regular in those AT coupes because they have a different performance profile...

Horsepower
Manual Transmission 298 @ 6,400 RPM
Auto Transmission 280 @ 6,200 RPM

Torque
Manual Transmission 260 lb-ft @ 4,800 RPM
Auto Transmission 270 lb-ft @ 4,800 RPM

those extra horses probably come from a higher compression in the heads. This higher compression is the price we pay for premium gas (no detonation).

So although the AT's may get away with it, the 6MT will likely start beating up the rings and pistons.