Hi Scotty, thank you for your videos.
I live in Toronto and my wife's chevy Malibu 2008's gas usage is too high. When we first bought the car 2 years ago the Short Term Fuel trim was fluctuating up to 10%. Since then I have used additives in the gas tank a couple of times to clean the system and it has now come down by about 5%.
The car uses up to 22L per 100KM in the city and car only has 113,000 KM on it. On the highway however, it comes down to 11L per 100KM.
What should I do and what can cause this?
Thank you.
For those who don't have a calculator handy, we're taking about 21 mpg vs half that in town.
Here's a converter
https://www.calculateme.com/gas-mileage/liters-per-100-km-to-us-mpg/11
That's not good. People are getting more like 25 mpg, overall average.
https://www.fuelly.com/car/chevrolet/malibu
A LOT of things can affect your gas mileage - where you drive (Toronto traffic!), who drives, trip length, etc.
Have you checked the usual? Plugs, air filter, leaks in intake manifolds, throttle plate and mass air flow meter clean, codes for misfires, etc?
Thanks Glen and sorry for the late reply.
There are no codes, I have cleaned the mass air flow sensor, and have replaced the air filter.
I haven't checked for intake manifold leak or the throttle plate. I will do those and see if I can find anything.
Could a faulty sensor cause this? should I replace both bank1 & 2 sensors?
Could a faulty sensor cause this?
Possibly.
should I replace both bank1 & 2 sensors?
Why not test them? For that matter you might want to look over live data for problems. (What do your fuel trims look like?) With computer controlled cars if there is not a simple, obvious cause for a problem the next step would be digging into the data.
