When I bought the HHR last week it was empty, so I stopped at the gas station and filled up with regular unleaded 87 octane. Upon reading the operators manual it says to use 91 or better octane?
I haven't noticed any pinging or anything so is 87 ok or is there a reason behind it? Honestly I don't know anyone who fills with premium even in their sports cars nor have I ever gotten premium in any of my vehicles in the past with no issues ... But if its best for this car I can use the higher grade at the next fill up, just wondering as I stumbled upon this.

 

I run 87 octane, 2.4 VVT 2011 , no problem averaging, 31 mpg.

 

I bought mine a year ago and thought the same. I went on a 5000 plus mile trip last yr and tried premium and it made no difference in the way it ran. Mine runs great on 87. Cheers.

 

93 octane here... But, I have a tune.

2007 2.4L, the manual said hi-test "recommended" (not to be confused with "required")

 

The SS ran a lot better on Premium, although I never stuck with the 87 to find out if it eventually adjusted. It got an accidental tank or two, and it was noticeably laggy.

 

I still need to change the plugs, Id like to see how they look if they've ever been changed? But they can also tell how the fuel is burning as well as other issues. I myself think it should have a little more power, and was wondering if the fuel played a role ? Past experiences just showed oil changes and new plugs pepped it up. Looking to get the best mpg out of it ( downgraded from a 2004 Ram 4x4 )

 

You are running lower octane fuel. In order to avoid detonation, the ECM retards the timing. This can affect performance.

If you are driving like you want to get higher MPG, then regular gas should be fine. If you drive more aggressively, you will get a little more out of premium, or even midgrade. You have to decide if the higher fuel cost is worth it.

 

I suggest you reread the fuel section in the OM. 2.4L it is SUGGESTED NOT required.

 

Im 52 so I drive normal, my hot rod days are over. Just looking at ways to make this little gas sipper sip better. Planning a few road trips with my son (9) one trip will be about 450 miles one way and undecidd where the next leg will go after that... as we will probly be on the road for a couple weeks with a few camping stops and overnight stays at a couple of the designations. Should be plenty of room in the back for all our gear and tools. One reason I got the HHR is my truck would have ate me alive in gas $60 fill ups and only 250mile a tank, where this little beauty fills at $26 and from what the dash says close to 375 miles+ until empty ( and I reset it a day after the fill up looking through the manual ) so she seems to be accurate hopefully. I may get a small trailer down the road as I may move, but mainly for small trips when needed or to get materials since the truck is gone. So far after a week I am enjoying the HHR, small but serving its purpose !

 

I use the AC Delco iridium spark plugs as recommended and have no trouble going 450 to 500 miles in the hi way either towards Florida or Cape Cod , our long hauls or just a couple of hours to Erie PA.