I went with the 2.2. I was wondering if anyone has had the chance to drive both?

we drove both - liked the 2.4 better - just had a little better pick up for us - been used to driving a miata and a v6 explorer

I have the 2.4 engine in my HHR, and love it. I was skeptical at first as most are, but after driving the car with automatic transmission was pleased. While in a passing situation at 50 MPH I floored the car and in seconds was around the passed vehicle and back in at 75MPH and a car length ahead of passed vehicle. You have to watch out, if you don't you will get a speeding ticket.The car seems tame at lower speeds with what seems to be slow acceleration, but when you press farther down it kicks in with wheel spinning power. I know I had it happen yesterday, while accelerating from stoplight i pressed down faster then normal and spun the tires. Don't like to do that, tires are expensive and I don't like to wear them out any faster than necessary. The power of the 2.4 litre engine is there when you need it, the car is not ment to be a dragster. :p

I did not consider anything else but the 2.4L... it was my first "must" and the second was Sunburst Orange! :D

Are they suppose to be the same gas mileage if driven the same?

Just like Parky I was skeptical myself of this engine. I was used to the power of a 5.3L on my Avalanche. So far so good, If you put your foot on it, it will kick in gear quick an take off, no doubt. Though the this engine calls for 91 octane while the 2.2 calls for 87. I've been running 87 on mine so far everything is OK. I think I will add octane booster to make up for the lower grade. Though I've been told it could mess up the engine. Have not done it yet till I get opinions from folks who know engines well.

Well here is some info I could find on the engine 2.4L

This brochure says to use regular unleaded
http://www.gm.com/automotive/gmpowertrain/events/racing/ecotec_24L.pdf

While a canadian chevy site reads "Premium recommended but not required"
http://www.chevyhhr.net/forums/newreply.php?do=newreply&noquote=1&p=289

The manual states to use 91.

I guess you could use both. Since here in California they seem to have hiked up the price of gas like crazy. I'll be using 91 when I can afford it and 87 when I'm broke. :D

supposedly both engines get the same gas mileage.

Does it help a car at all to use better octane gas? If so what does it do?

About 0.01 second faster to 60... not worth the extra $0.20/gal for premium.

Does it help a car at all to use better octane gas? If so what does it do?


In the owners manual it claims that if you use anything less than 91 with the 2.4l then your acceleration will be slowed and you will hear a knocking noise...

I've been using 87 octane in my 2.4L and I will admit that recently after I turn of the car, I do hear pinging. Next fill up will be with 91. I'll let you know if the pinging stops.

Been using 87 since day 1 and no knocking.

I agree 87 octane since day 1 and no pinging, buy my gas at Indian Res with no problems in engine. 2000 plus miles so far!

... buy my gas at Indian Res with no problems in engine.How much cheaper is that?

Maybe I'm mistaken, does the pinging sound like little rocks hitting the inside of tin can? Kind of like tick, tick, tick tick, tick after the engine has been turned off a couple of minutes.

Maybe I'm mistaken, does the pinging sound like little rocks hitting the inside of tin can? Kind of like tick, tick, tick tick, tick after the engine has been turned off a couple of minutes.


I don't hear anything after I turn mine off, (I have the 2.4L). Try changing your gas, just too see, it sys that after you run the 91 or higher for a bit it should stop, if not take it to the dealer....but let us know either way, I'm curious on this....

I don't hear anything after I turn mine off, (I have the 2.4L). Try changing your gas, just too see, it sys that after you run the 91 or higher for a bit it should stop, if not take it to the dealer....but let us know either way, I'm curious on this....

I think I will do that. I'll try the 91 and see what results I get. I'll be taking a nice 2K road trip next week so I'll definantly experiment with octane levels.

Will post results upon my return :D

Gas at the Indian Reservation is around .25c a gallon cheaper. 87 Octane.

Maybe I'm mistaken, does the pinging sound like little rocks hitting the inside of tin can? Kind of like tick, tick, tick tick, tick after the engine has been turned off a couple of minutes.

That possibly is the exhaust system cooling down, mine clicks/ticks after shutting off also. It is no problem, just a hot metal cooling down.

Usually Better Preformance parts for the engine come out for the better engine.

That possibly is the exhaust system cooling down, mine clicks/ticks after shutting off also. It is no problem, just a hot metal cooling down.

Thanks Parky, that is exactly where it is coming from :)

I guess I have not been getting any pinging than. So relieved :D