As the title says. Went to my local tesco today to fill up as usual but once I had filled her up I noticed the super unleaded on that pump had changed to 97 ron instead of the usual 99. It was a new sticker on the pump so I asked the woman behind the till if it had been changed to 97 or if the sticker was wrong and low and behold she had no idea. Anyway I drove about 20 miles and everything seemed fine but it was really worrying me as my car is a jap import and should run on at least 99. I stopped at the nearest halfords and got some octane booster and fired that in. After about 10 miles I got stuck behind a tractor so I gave it some welly to get past it. Pretty much straight after that a sorta rythmic noise started, Really hard noise to explain, I immediatly took my foot off the accelerator but it didnt get any better. I put her into 5th gear and went as easy as I could till I found a place to stop. I pulled over and had a look around the car incase it was something else but I couldnt see anything, I lifted the bonnet and had a listen under there but again couldnt hear anything. I then drove home and never heard it again although I took it easy all the way home. Normally Id think it was just me being paranoid but the mrs could hear to which is unusual!

So.....Can you hear an engine knocking or is it something else going wrong

 

you can hear knock or det if it is very bad, i would take it easy till you have used that fuel in your tank and run some decent fuel through it, and hope no permanent damage was caused.

 

if your engine is knocking you would know about it mate.

 

Thats what I thought but im bricking it now lol. It was definetly a noise Ive never heard before.

 

yes you can hear det once it gets bad enough, sounds like a kind of tinkling noise from the engine and happens obviously under load, from your description it doesnt sound like this is what you heard, however as above use the 97ron gently and refill with 99 once you can

 

this sounds like the scoobynet scarmongery has gotten to you.
if the engine was goosed you would know by now.
if its a pre 96 import then 97 ron is fine anyway.

 

can' you put octane booster in it?

 

Read about engine knock on imports using our crappy fuel before I joined scoobynet, Its a my01