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Honda Civic 2008 Hybrid poor MPG arround 29.4 !

10K views 20 replies 5 participants last post by  HELMI BEN KHALIFA  
#1 ·
Hi Guys, I have a Civic Hybrid 2008, it has a problem with the hybrid battery, no Auto Stop was working, and it has very poor acceleration, the fuel consumption was about 10l/100km = 23.5 MPG.

Now, i fixed the hybrid battery by replacing one of its 11 modules, it was a damaged one. Now the car has better performance ( acceleration ) and thanks to the Auto Stop it has a better MPG ( arround 29.4 ), But i think it is a poor MPG for a hybrid car.

So i continued replacing and improving the car,
I changed :
  • Air filter
  • Spark plugs
  • Engine oil + oil filter
  • 2 O2 sensors
  • MAF sensor
  • CVT oil
  • Fuel injectors

But I'm still struggling with that poor mpg ( 29.4) :( do you have any idea what may be wrong?: /

Thank you
 
Discussion starter · #5 ·
I have changed only one module of the hybrid battery, now i think i have all the modules balanced, but they are old, so the battery is charged and discharged quickly. But i feel the assistance of the electric motor ( good acceleration ).
Image

You can see in the discharge curves how only one module is damaged ( blue one ), the other ones have same discharge behaviour.

I'm using my civic in the city, I know the mpg is low in the city but what about the electric motor and the hybrid system ? why i'm getting an MPG worse than normal cars ! ( Not hybrid ).

When i drive it, I noticed that the car is consuming a lot of fuel the produce small power. For example, on a flat road to keep the same speed, ( 50 km/h for example ), the instant fuel consumption is 6.5 l /100 km = 36.18 MPG. I think this is weird.
 
Discussion starter · #11 ·
I checked the brakes on all 4 wheels, they don't stick. The car continues to move with minimal friction when I put the transmission in "N".
I have a doubt about something clogged, which prevents a normal air flow, By the way, in another post I posted the picture of the spark plugs that I removed, and everyone to me said the car was running too rich ! This is the picture :
Image
Image


Does that confirm my doubts? If so, can the catalyst get clogged and cause this type of problem?
Thaks
 
Discussion starter · #13 ·
Is your check engine light (cel) on?
If so, read the ecu's error-code(s) with an obd2 reader.

If not, try to read the real time ignition timing the ecu uses. You also need an obd2-tool for this, plugged into the obd2 port, and monitor it during driving, for instance use the android torque app on a phone.
No, i have no check engine light on. I will see if i can get that information of ECU timing. ;) Thanks
 
Discussion starter · #14 ·
@Sondair I have scanned the ECU with OBD and the only info that contains "timing" word, was "timing advance", the value was arround 8° and 10°. I can't understand the unit of this value.
Also i have here some values from the ECU at Idle, i want to show you the picture, so maybe anyone notice that some values are weird.
Image