Bad gas mileage?

AARONCAVY

MEMBER
2006 CHEVROLET HHR
4 CYL
FWD
AUTOMATIC
76,000 MILES

I have lost considerable gas mileage over the past few months. I usually get 400 miles on one tank, I am almost at half a tank and its almost at 100 miles. When I rev the car I hear something different like something is lose. I would like to know what could be the cause of losing such considerable gas mileage. I have had the fuel filter, air filter, and tires changed in August so this cant be the problem. I think it could be the exhaust? Let me know what you think it could be.

1 Reply

HMAC300

MECHANIC
48,601 POSTS

Have the engine scanned for codes, most auto parts stores do this for free or you can use this guide.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

if it 's the exhaust you need to put a vacuum gauge on it to tell. I'd bet you have a MAF sensor that is bad and is why your mileage is dropped so dramatically.

You can check the catalytic converter using this guide.

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Check out the images (Below). Please let us know if you need anything else to get the problem fixed.

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