[mattwa]

Sometimes when I'm driving in heavy rain the speedo starts to flick downwards about 10 MPH then goes back up to the speed im driving at. It's like...flick..flick.....flick. Could this be water shorting the VSS out or something? Oh, im not sure but I think the faster you are going the worse of a flick it gets...like on the highway once it totally dropped to 0 MPH and didn't move for like 30 seconds...while that happened the Odometer also stopped moving..but It came back up. Any ideas?
Thanks
Matt

 

[5766]

im guessing the vss is bad, or the connection is going bad.

 

[Nidan]

Sounds like the VSS. A friend's sable also has a problem with the speedo dropping out after he's been driving a while. I monitored the VSS PID and could watch it start cutting out as he drove. I don't know if he's gotten it replaced yet.

 

[mattwa]

yea I just learned that the V8 SHO has no VSS..its all ABS..

 

[shoz123]

Either there is a bad wheel sensor or the ABS module is going bad. I bet it's the module that is going out.

Mine did. The symptoms would be the ABS light start to flash and the speedo drop out completely usually to come right back on. But it eventually failed 100% and the PCM really gets stupid then.

Unfortunately this was a first place winner in the Engineering's Division of "How to mount it in unused and inaccessible places" contest. Extremely difficult to get to. Under the battery tray.

The electronic module can be removed from the pump and valve end. In theory anyway. Ford uses some grade 3 Torx head bolts to secure it with one large one in the middle that connects to the pump body. This could not be removed so I replaced the whole thing with a used on.

Avoid '98 ones if you can but they are all interchangeable among Gen 3 SHOs..

 

[mattwa]

If possible, could you give me more detailed instructions on how to replace this module? What would be the cost of the new part etc.? Also, do you think a bad ABS module would drain power from the battery at all times? Because I think my SHO does have a battery drain but I dont know where it could be. I did check the mAmps after the car sat for an hour or so..and i got a reading of 0.16 mA?
Thanks
Matt

 

[shoz123]

New part is +$1000. Difficulty level to change out 9 out of 10.

Drop the motor and transmission out. (Not necessary but sure is easier.)

Then loosen the 4 brake lines going to the ABS. Bend the two from the MC up so they do not drain the MC.

Disconnect electrical connector.



Take three mount bolts out of frame.

Remove unit.