Trip computer display problems sensor problem???

[timuss]

Am unsure about this so here goes! I have what i believe could be an issue with my car firstly my MPG has dropped i had been comfortably getting 29 mpg + But since filling up recently it has dropped to around 26 sometimes less than that. There are no error codes that i have noticed the car seems to be running fine.

And lastly my average speed display currently reads 15.9 that doesn't seem right to me at all considering i'm usually doing comfortably 30-40 on my daily commute. Its a four mile journey i should be seeing a better return on my MPG surely?? And the speed display should read higher maybe??

I did have an issue with the display when i had my cambelt done, and the car was displaying as only getting 22 mpg and no more. That was resolved when the garage did a reset i believe and it came back to normal, Could there be a sensor issue somewhere.

I am a complete novice to car maintenance and any help and advice you can give me is very much appreciated, before i consider getting it looked at.

 

[JBC27]

Wouldn't worry about average speed as things like junctions and traffic lights mean its fairly meaningless.
My speedo sensor was intermittent for a while and the effect of that was awful mpg as the car thinks your not moving but knows the engine is burning fuel. Also trip stopped registering miles traveled and the whole speedo would cut out. Needle would drop to 0miles per hour.
You can get a replacement speedo sensor for about 15 off eBay. Cheap to rule any issues out...

 

[timuss]

Ah ok cool, everything is working fine touch wood, thanks for that.