I've just recently noticed that at lower RPM's (1500-2500), if I decide to press alot of gas, the car rattles up front. I used to have this on my 2000 Z24, and my 95 swift. I believe im just noticing this because the weather is warm enough for me to have the windows open to hear. This sound is normal for some cars because you are putting more gas in then the engine is ready to use. Does anybody else have this problem? Just so you know, its easiest to hear between 1st to 2nd, and 2nd to 3rd. Let me know what you all think.

Thanks.

 

That's knock, ping, detonation. Buy higher octane gas or kiss your engine goodbye.

 

What grade of gas are you using?

 

Wow, forgot I used lower octane this fillup because I was driving a long distance, and didnt want to spend the money. Ill try better gas next time. See what happens.

 

I think I have the same problem as you do but I didn't really pay attention to it since it's really minor. I used 94 ever since the car was bought and it definately is not fuel-dependent on this problem.

Does your car rattle really bad or it's really minor and you can barely feel it?

 

Not major Just yet, but I know it recently occured. My last 3 fill ups have been cheap gas. When I empty this tank, I will use 94 octane and see what happens. I've seen this on so many cars though.