Hi there,

I have a mk1 fabia VRS on a 54 plate, I was consistently averaging around 56.7mpg which was great however it was quite smokey.

I since put one of those fuel sensor chips on (one of those resistor types that plug into the fuel sensor and rail) which did increase the torque and made the car feel more responsive. The mpg again was similar if not better, however was starting to smoke quite badly after a month or so of running the chip.

I removed the chip to try if it solves some of the smoking problems, and it has. However my car feels quite flat compared to how responsive it felt with the chip....the idea of a chip I am sure. The problem is now my average is around 47mpg and I struggle to maintain 52ish mpg on the motorway runs.

Any ideas? Can the fuel economy computer be re-calibrated?

Adam

Are you sure everything has been connected back up since removing the "chip"?

it was literally just the fuel sensor from the rail which you plug it into. Obviously I have clipped that back on but will double check tonight and make sure I have clipped it back on properly

One other thing....

Are you sure you're driving the same as before?

Since your power decrease, you could be putting your foot down more to compensate

Check the maf, coming to crappy time of year more muck gets sucked up, check for boost leaks those boxes put more pressure on the pipes.