a1320honda

im running a really low octane gas (87), and today it was really hot, and at idle there was like a kind or almost rattling type of sound from the bottom end. so i put some of that engine restore stuff in, and some 89 gas and it seems to be gone. but i hate the sound that was coming from the engine. i have the jdm d15b vtec. is that what it was. the rattle was like loose valves except a little bit louder. and didnt do it while getting on the gas, just around 1000 rpm on decelerating. so wtf is this noise? like i said, i dont know directly what detonation sounds like. any clues anyone? i also just changed the oil last friday. and since then it seems harder to start. but maybe thats just me.

93Civac

Detonation would be a boom sound (correct me if im wrong). It sounds more like you have spark knock which is caused by the low grade of fuel.

You may want to chech your oil level just in case, and what weight oil did you use?

Kamin

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93Civac &raquo;</TD></TR><TR><TD CLASS="quote">Detonation would be a boom sound (correct me if im wrong). It sounds more like you have spark knock which is caused by the low grade of fuel.</TD></TR></TABLE>
detonation makes a pinging noise.

Shawn C

iTrader: (1)

makes a pinging noise, or if you're running lean at 6500 rpm on 14 psi of boost, it sounds like POP POP POP!!!!!!

a1320honda

i used castrol 10-w30 synthetic blend. i checked the oil. and it was over the full line. it was a very distinct rattle sound coming from the botom end, but it isnt doing it now.

TRF #001

possibly developin a small rod knock or on ur way to a spun bearing. i had the same noice in my old rex. sounded like sum loose valves till one day i was goin down the high way and it got louder n louder till a rod came through my block. just my opinion since i had the same noices

a1320honda

but wouldnt it start doing it all the time. like i said, its not doin it now. i just went out and started it up and it sounds normal. sounds good actualy. and what are the chances that it could happen on a motor with only 38k on it.