Ford Scorpio Forum - Print Page


    
      
        Ford Scorpio Forum
        (https://www.fordscorpio.co.uk/cgi-bin/yabb/YaBB.pl)
      

        General >> Problems >> 2.0 16v Auto gear changes
        
(Message started by: Highlander on Sep 10^th, 2005, 5:00pm)

Title: 2.0 16v Auto gear changes
Post by Highlander on Sep 10^th, 2005, 5:00pm

94 2.0 16v Auto Estate, bought it two weeks ago for spares or repair

car has done 150,000 miles
gearbox oil level is ok
Oil reddish brown
Maf cleaned and tested ok
Definite cracked wiring present in various locations round the car. (pre 96)
Engine runs/idles perfectly.
Fuses and fuseboxes checked and ok
Scorpioman did an OBD scan for me which didnt throw up any relevant codes (thanks Andrew :D)

Problem

reverse gear works only very rarely, when it does work it will quite happily go through the gears fine until the engine is turned off again.
Sometimes when I pull away from standing it starts in second gear but will go up and down through the gears ok with the exception of 1st.
Most of the time it will pull away in 1st but fails to select top gear so the revs rise to 5000 at 70mph.
Once it has decided which of these its going to do it stays like that until the car is restarted.

Speedo is reading correctly but pressing the mileage reset button shows speed to be 50% above actual road speed. eg.

Speedo at 60mph, revs at 4000, display at 90mph
Speedo at 70mph, revs at 5000, display at 100mph

If i press OD button at the above speeds the revs rise to nearly 7000!

Its as if the car thinks its doing this display speed and is already in top gear..

Got an idea but would like your opinions

Title: Re: 2.0 16v Auto gear changes
Post by Snoopy on Sep 10^th, 2005, 5:02pm

I would have a look at the VSS on the side of the gear box , that is wher all the speed info comes from and the EEC takes it from there as well.

Title: Re: 2.0 16v Auto gear changes
Post by scorpio_man on Sep 10^th, 2005, 6:10pm

hi there

i wonder if it's the wrong VSS (if different for each engine?). if i remember right, they normally stop working, then work for another bit before dying. not at +50%. :-/

still doesn't explain the strange gear selections. or does it ;)

btw, i've had another look at the VE software and i've missed a bit out on your scan. next time you're over this way, we'll do it again. :)

Title: Re: 2.0 16v Auto gear changes
Post by Highlander on Sep 10^th, 2005, 6:23pm

will have a look at the VSS, going by the rest of the car it might either have cracked wiring or be hanging loose :)
could it be fooling the car into thinking its a gear above what it actually is? I mean if it were doing the speed on the display then the rev pattern is about what id expect it to be albeit it should be in top gear. (thats confusing isnt it :)

Title: Re: 2.0 16v Auto gear changes
Post by Danny_R on Sep 11^th, 2005, 2:34am

The VSS is the same for all Scorpio’s that have the A4LDE gearbox. Since the electronic solenoids in the auto box change the gears and receive signals from the computer which receives the vehicles speed from the VSS, I would say it is definitely the VSS at fault. One easy way to check if the VSS is faulty is to turn the Automatic Volume Control (AVC) feature on the radio to maximum sensitivity and take the car for a spin. If the radio volume fluctuates between loud and quiet the VSS is on its way.

Keep us all posted ;)

Kind Regards

Danny_R

Title: Re: 2.0 16v Auto gear changes
Post by Danny_R on Sep 13^th, 2005, 2:05pm

Was it the VSS Highlander?

Danny_R

Title: Re: 2.0 16v Auto gear changes
Post by Highlander on Sep 15^th, 2005, 7:07pm

Not had a chance to have a look yet, will try this weekend

PS i tried the dash speed reading on the 24v and its the same!
reads 50% above the speedo reading, im assuming both cars are showing the dash reading in Km/hr (with the 10% deviation from the speedo)?
Both cars fuel computers are set at MPH/MPG not litres/Km???