Rep Power: 0

So my 2001 Honda Civic pings in in the higher rpm’s . So I started running 91 octane in it about a year and a half ago. That totals stops it from pinging. But why would a stock 2001 Honda Civic be doing this? Only reason I think it’s pinging noise because it goes away when I run high octane.but comes back once I drain the tank a refill with 87. Since gas prices have gone up I’d like to go back regular gas.

 
Rep Power: 367

carbon deposits is one potential cause.
moved thread to mechanical issues section

 
Rep Power: 222

Yeah have a look in the combustion chambers, you can get inspection cameras pretty cheap now. No check engine light?

 
Rep Power: 0

Only check engine light I get is p1457 . I think that’s the code number I can’t remember . It says it’s a Honda specific code . I think it has somthing to do evap vent Solenoid. I only get that code once it getsto almost 3/4 of a tank that code pops on. If I reset the code and keep the tank full it takes about 300 to 400 miles before it comes back on. I’ve done a lot of experimenting. Thank you for confirming I was thinking maybe it could be carbon deposits on top of the pistons cause it to ping. Sorry for posting in the wrong section.

 
Rep Power: 222

Yeah evap related, wouldn't affect the pinging, are you in the rust belt?
does it burn oil?