Today I decided to finally find out why my speedo isnt working on my Mk1 Si, even though ive become so accustomed to it not that I know how fast im going by revs x gear.

Had a look down the back of the gearbox with the air intake assembly apart and found this 3 prong connection hanging out of the gear box, I presume thats for the speedo?



However I cant find anything coming from the bulkhead that should plug into that, where should it come from exactly?

If its not there and I need a replacement is it a job I can do myself?

 

I am pretty sure it is the speedo connector, from what I remember, just look to see if it goes to a speed sensor on the gearbox.
tabetha

 

Yes it does

I had a suspicion it had an engine change for a newer engine in its life and the dials were mechanically driven and the gearbox output electronically and the person who did the engine change just didnt bother with it. But I took the dials out to check and theyre also electronic.



both strip connections are present coming into the interior, what I need to know is where the missing link is - what does the speedo cable come from? obviously I know where it goes to as in the first picture.

 

AFAIK the speedos on mondy's were ALL electronic, NONE were cable driven.
Being EFI they would need an electronic speed impulse anyway for the cu.
Mine was a "M" reg, but can't see other being different.
I am waiting on someone phoning me back to confirm though, as he breaks focus/mondeo's
tabetha

 

Mk1's were all cable driven and Mk2's onwards all electronic.

They changed at the same time that the gearbox went from rod to cable change and non hydraulic to hydraulic clutch.

 

How would the car behave if it wasnt getting that speed impulse if it was a Mk2 ecu? would it judder randomly for a period of time then go off again for as long as you drive the car? because thats the problem im getting.

Im well in the belief that the engine has been changed for a Mk2 engine and box and theyve swapped the dials over so they havent bothered with the speedo cable.

Three reasons for this

1: The cambelt cover had 45,000 written on it in tipexish stuff.
2: The cam cover has "Zetec16v" instead of "DOHC16" which I think is odd for a 95 "N" car
3: There is a hole in the plastic behind the dials where the speedo cable would have come through (for all I know the Mk2's could still have this)

The problem is I dont know whether its using a a Mk1 or Mk2 ecu but I suppose either way it could be causing the juddering.

Mk1 ecu not liking the MK2 engine differences
Mk2 ecu not receiving speed impulse

Where would an electronic speedo cable come from? the ecu? Im a bit stuck for how to resolve this.

I could fit an analog sensor, cable and dials but that wouldnt help my juddering problem?

 

Anyone know how I could find out whether its the original ecu or a mk2 one?

where is it? lol

 

wrong!!!
early mk1's 93/early 94 were cable speedo, they then went to electronic around the same time the v6 was introduced
and as said they changed at the same time as the clutch to hydrolic,

I break mondeos hence my knowledge of them.

steve

 

Looks the same set up as my Escort, the speedo is cable driven but there's a speed sensor attached to the gearbox end. The other part of the loom should be near the starter motor.

 

Right mate, would you say my 95 is definetly electronic speedo? also should it say zetec16v on it or the old style dohc16?

Leeeroy, thanks I will have a look for it - if its something simple ill be very happy.

 

My MK1 2L GHIA auto was DEFO ELECTRONIC, was a 95, on a M.
Mondeo/focuspart never rang back with info!!
tabetha

 

well i have a 1995 mk1 v6 and mine has cable speedo but hydrolic clutch