My '95 Legacy auto (102K) pings under part throttle between 2,000 and 3,000 RPM. No codes, it runs fine otherwise. Gas mileage consistent, 23-26 MPG. I put a new air filter in 6 months ago. The spark plug wires have about 9,000 miles on them (OEM Subaru wires).

 

It doesn't seem to matter where I get gas (Sheetz, Sunoco, Hess, Wawa). I've added a bottle of techron fuel system cleaner to this current tank; didn't help. Would seafoam be better to try?

 

Any other possible causes? The spark plugs have almost 20k on them... could it be time for new ones?

 

Thanks,

Brian M.

Hey! Another one in PA... and not too far away. Something doesn't sound right. I've got 190k on my 95 and it never pings. My wires are aftermarket cheap ones, and my plugs have 20k on them. I get gas where ever it's cheapest, which lately has been Giant ($2.45 last night for 87! Most places were $2.49 to $2.59) I'm not really sure what would be causing it though. Maybe a reset of the ECU is needed? I know the newer OBDII ECUs learn their timing curves. It was what caused the major pinging issue in the first released STis. Anyhow, something sounds wrong to me, I just don't know what.

 

Keith

I am having the same problem as you & it happens to me also between 2,000 & 3,000 rpms when I acclerate & go up inclines. I have taken the car to the dealer & they said everything is running fine & it's under warranty but I am still not satisfied so it's going back in on 4/10 so I'll let you know what they try to tell me this time. I have a 05 Impreza 2.5 RS SW with only 6,500 miles so that's why I find this to be odd.

As they say in Detroit:

 

"Light spark knock is the sound of economy" which is where the engine is running at it's most efficient settings. Detonation is a whole nother matter.