Engine pinging - New Forester

[JM]

Have had my new Forester (had WRX) a little over a month. So far really
like it. However, have noticed the engine pinging a little when driving
on a fairly level road and then starting into a very slight upgrade.
This occurs mostly in 4th or 5th gear with and without cruise on.

I live in Washington state so we have a lot of these slight uphills.
Have tried various brands of gas and they all appear to do the same
thing. Trying Chevron now and so far so good.

Took a trip to Teton a couple of weeks ago and the pinging stopped while
we were there; even using the 85 octane gas they sell in Wyoming.

Has anyone had similar problems? Any solutions?

TIA

 

[Edward Hayes]

This is normal on my 2000 Forester S. Timing is being advanced to the
max for the fuel used for max efficiency. If my Forester stops this at
88,000 + miles I'll know something is wrong.

 

[Steve]

However, have noticed the engine pinging a little when driving
on a fairly level road and then starting into a very slight upgrade.

I think I've also noticed this (2005 Forester X, manual) on two
occasions with situations similar to what you describe. I was in 5th
gear with RPMs low, but not so low I would have expected pinging.
Easing up on the accelerator or downshifting to 4th made it go away. The
pinging was slight and it would have been reasonable to have been in
4th rather then 5th at the time, so I didn't pay it much attention. But
your post is making me think about it. I'll watch for it to occur
again.

 

[Edward Hayes]

Light pinging is very normal for the conditions you described and the
ignition timing is being advanced to achieve maximum efficiency. Mine
has done it since new and now at 88,000 miles. If it quits this I know
something has changed for the worse. ed