MFA MPG Query

[smithysmoo]

Mine is showing something between 6-8mpg obviously wrong big time as I'm not filling up every five minutes.... Any ideas how to get it more accurate or what might be the problem.


cheers

[rubjonny]

could be the vacuum hose on the back of the clocks has fallen off, or is doisconnected in the engine bay.  Do the avg speed & miles travelled settings work on the MFA along with the rev counter?

[smithysmoo]

Yep all the other settings seem to work ok..... Will check in the engine bay then and see what I can come up with.... Otherwise suppose I gotta try and take the clocks out.

[JimR]

Mine was exactly the same, it was the vacuum hose that is attached to the pipe on the top right hand side of the inlet manifold had become brittle and cracked, although mine ran like a bag of spanners aswell. Renewed the hose and et voila.

[hexomire]

i got that problem too. but i have the metrical mfa. the mfa fuel usage reads 15.5 l/100km but if i calcuate it myself its between 10 and 11 l/100km. so it lies about 5 l/100km. are in my case also the vacuum pipes or something else?

[Lap]

Same as what mine was doing. Found out that somebody had disconnected the vacuum hose from the engine and corked the ends. No idea why.
Once re-connected, my mpg read 30 (ish) instead of the previous 8. 

[smithysmoo]

Well found a clear plastic tube that ain't going anywhere so I'm guessing this is it. But where do I connect back to. Anybody got a pic or something. Cheers

[JimR]

I'm not sure what engine yours is, but i think the hose you mean plugs into a black pipe on the right hand side of the inlet manifold, slightly above and to the right hand side of the breather on top of the rocker cover in this photo

[smithysmoo]

Yeah thats my engine and looks like my car except yours is cleaner. Only had mine a couple of days and ain't had chance to get it spick and span..... is it the bit where I can see like a yellow connector as this is where I thought it should go. There are a couple of holes that could be the ones but they are covered up.

[JimR]

Thats the one, i think you should see two vacuum pipes, one will be bunged (they are all like that for some reason) and the other is where your hose wants to be. (by the way, its not my car either, i wish mine was this clean but it was the first PB engine pic i could find in the projects section )