Oldblue

Have a look at the MAF location and the tube size as suggested

843de

You might, and that's just might want to give it what we call a Lobotomy here.

Disconnect the NEGATIVE battery cable, can't stress the NEGATIVE battery cable part enough, then walk away for a while....five minutes is the absolute minimum.

Then reconnect the NEGATIVE battery cable and just drive it normally, it might feel a bit different in throttle response and shift points(if its an automatic), for a few days.

What disconnecting the battery cable does is to trigger what is called a "Learn Down" mode in the PCM/ECM and that will reset the fuel trims to the factory defaults until your HHR adjusts to the new intake, etc.

Once it's learned your driving style again, and it adapts to the modifications, your gas mileage should bounce back to where you'd expect it to be.

gio89kid

What?

The maf sensor is facing the correct way and installed correctly. And I already reset the computer with the negative battery cable and waited 30min when I did it.

And before I got the intake, the dash said 22.5mpg, I don't know the actual calculated, but now after it says 22mpg and 22.7mpg calculated.

If the dash was correct before, I'm getting near the same gas mileage.

So what are you guys saying?

Oldblue

Sorry for the confusion, I thought you meant 22 mph was low for you, and were asking for further assistance.

843de

X2 to what Oldblue said, we're both from the breaker point ignition and carburetor era, and I was confused too.

So for the sake of the gray hair and reading glasses crowd here, including me, were you expecting a gain in gas mileage from a performance intake?

Usually it stays pretty much unchanged, to dropping a smidge.

Using my '07 as an example. After the installation of a GMPP Performance Intake and Exhaust(made by Borla and stuffed into boxes labelled "GM"), the overall fuel ecomony numbers improved approximately 4% on the highway, and they stayed the same in city driving(as long as I don't drive it like a hooligan, which is difficult to avoid doing, with that lovely combination of intake 'Snort' and exhaust 'Bark')

So perhaps some clarification is in order, maybe.

gio89kid

It's fine now, but when I first installed it, it was burning a whole lot of gas, way more than normal. But now it's doing just fine. :)

The initial consumption of gas was worrying me, but now that it has the correct trims, it's all good.

gio89kid

Hello all, and thanks for the help this far.
I just filled up on gas again and calculated the mpg and it is 22.39mpg which is what the dic is telling me.

So just like before. But then I reset the dic while in town and it went to like 17mpg ave, then I took my trip to school which is DOWN the big hill and averaged 23mpg.

Also at a stop I turned on the A/C and the rpms kept bobbing up and down.

So my question is, what is causing me to get bad gas mileage since the intake doesn't seem to make a difference, could it be something related to when I turn on the A/C and the rpms go crazy. Some sensor or something.

I hear a lot of people get good gas mileage almost 30 mpg in there hhr, mine is basically stock except for the intake, what would be causing my gas mileage to be bad.

Please advise thank you.

Oldblue

Run 6 or 10 tanks of fuel and don't reset the DIC on anything, give a more true average of your fuel readings

gio89kid

Yeah, but before the intake I never reset it that often and after the intake I'm still showing the same gas mileage. 22.5mpg what could I check, like sensors that could improve the gas mileage?
Also, rpm fluctuation when turning on A/C, can that be related to a sensor. I mean it goes from 1000rpm to 500rpm and bounces until it levels out. And sputters when it reaches below 500rpm. Sensor somewhere?

Grizzly old man

There should be somewhat of a dip in RPM when you turn the air on. Turning the air on makes the air conditioning compressor start to engage which causes the engine to work that much harder.

That's why a lot of older folks don't use their air conditioning. They are convinced that they need those few horsepower that it takes to run the air.

A lot of us older folks will just open a window thinking they are saving fuel by not running the AC but in fact the drag from having the window open cost them more in fuel.

Took a long time for me to convince my wife and her dad that its really cheaper to run the air than open the windows.

Yes running the air does take a bit more fuel than not running the air but I like the comfort of having nice cool air in the car especially on a long trip. Its up to you if you want to get that fraction of a mile better MPG or if you want to sweat I guess.