I think when they recommend a certain octane,.. they mean you cant go below what they recommended. I don't see how using 91 or better octane can be bad for your ride.
In my 5th gen,.. If I use anything other than 91 and better,.. I get serious pinging.
I use good fuel and the noise goes away.

 

Did you advance your timing? I believe changing the timing may require a higher octane to avoid pinging.

 

can also be climate....

 

I had never heard that. I know that the timing can cause pinging if you use a lower octane. He says that he gets pinging with a lower octane, not that he pings in winter but then it goes away in spring. How does the climate affect it?

 

I have a 96 Accord EX (w/ 2.2) and my manual recommends 87, however my engine also pings like a mofo unless I use 91 or better. I even tried using 89, and it was detonating really bad so I switched back to premium immediately. I'd love to be able to use a lower octane (save $$) but I'm not going to risk damaging the engine over a few cents. I've gotten a tune-up, replaced the fuel filter, did numerous fuel system treatments, etc. with no results. The only thing left to do is retard the timing. The service tech at the dealership told me my car has spark knock sensors, which automatically retard the timing if they sense pinging... but apparently, they aren't working! Also, my best highway mpg has been consistantly 29..even after the major tune-up (which included new fuel filter and fuel system treatment) the car is an automatic. Does this sound right?

 

Yeah. retarding the timing would be a way to make it stop pinging on lower octane fuel. I think it would also help on your mpg. Advanced timing makes the car more peppy (correct me if I'm wrong.)

 

use rubbing alcohol.

I notice the difference when i use 87 or 91.
Its a miniscule change but my accord isnt a freaking race car so it doesnt matter.

One thing i do notice is that when i use 91 octance my car doesnt burn that much fuel.

 

My sentiments exactly.
I rarely miss a tune up, and I'm always on top of my car.
I would also like to save money on fuel these days,...but not at the expense of detonation.
I say 91 octane would be ideal for todays modern cars.

 

Oh yeah, when you do run a FI cleaner through, you may want to get a tank of higher octane gas when you dump the cleaner in. The higher octane will burn more completely in the chamber helping to make the most of the cleaner.

 

I didn't say that all gases did not have detergents. I said running a higher octane tank through once in a while would help clean. I said this because a higher octane fuel burns more efficiently thus more of the fuel is burned in the chamber and this CAN help keep it clean.

Using higher octanes CAN cause your car to run more efficient too because more of the gas is burned/ignited in the chamber so more of the fuel is being burned instead of going out your tail pipe, which means potentially better gas milage too.

Unless your car calls for it or it's performance is decreased, it's not worth the extra cents. Some cars require it.

If you're experiencing "pinging" or detonation, it could also be the wrong heat range on the spark plug if you happened not to put back in exactly what is recommended for the car. The wrong heat range on the plug can have an affect on performance.