mfa stuck on 99.9mpg

[Diluxe]

Hi my 89 16v has a MFA computer thing upuntil about an hour ago, it was working fine, now on setting one the mpg is reading 99.9 all the time, all other display patterns seem fine time,speed etc and everythings working fine on setting 2.

any ideas whats up?

cheers

[Gozza]

I have heard if you disconnect the battery for a while and then reconnect they sort them selves out. Worth a try me thinks  

[Blue MK2]

the vacume hose behind the speedo has probably come off. Plug it back in.

[mk1]

I may be wrong, but if the sensor was working correctly, a low vacuum (sp) will show a poor mpg?
Steve.

[Blue MK2]

happend to mine till i reconnected the hose.

I think its reading 99.9mpg because its got nothing to calculate hence the hose has come off?

There have been a few posts about this.

[Diluxe]

Hi,

thanks for the hints, had the battery disconnected for about 3 hours, everything reset to zero, all reading read -- -- - for about 5 minutes and then i went for a drive around the block, and everything but the mpg on setting 1 and 2 seems not to work and is stuck again at 99.9 mpg

so i guess it must be this vaccum hose, how easy is it to get to the back of the dials? and is thereanything i can do to keep it on , and even more importantly what made it come off?

cheers

[Blue MK2]

You have to unclip all the switches first. Take the headunit out also.

Once all these are out of the way you will find a few screws (about 5-6) located behind the switches. This will be clear once you have taken the parts out.

There are 2 screws near the top of the speedo and one behind the main light switch.

Pull the dash surround out and there will be 2 more screws that old the speedo in place

Pull the speedo out but try and keep the speedo cable in its place. Refit the hose and your done mate.

The hose probably came off if it was pulled from the inlet manifold

[JezGTI]

Where abouts in the engine bay does the vaccum hose run?  I have --- on MPG, Miles and Average Speed but the vacuum hose is definatly firmly connected to the back of the speedo.
By the way FYI Diluxe, I found that it was impossible to remove the clocks unit without removing the speedo cable (which is a bit of a b!tch, had to reach around with my right hand and squeeze the plastic arms on the connector plug).

[Blue MK2]

I havnt had a good look for the location of the hose but its around this area (see pic)




Hope that helps

[Diluxe]

Cheers Blue & Jez,

I was just about to post, the following reply "before I dismantle the dash, is there anywhere in the engine bay i should check that the hose has not come loose or split"

but you've posted up a picture so   , what engine is that i guess thats not a 16v?

also I recently changed the air filter could i have screwed something up there, I notice that on the top the air filter box is a big round thing with 5 or so braided cables coming out......................................

cheers