Right...when i unplug the rabs it ****s fine ( just dont have speedo....odom...or who knows what else...) .... No i didnt check air gap...dont know how....how can that be altered if there is no adjustment on the sensor or the tone ring?...just cutious

 

Some have shaved some off the VSS so it will set deeper and lets the VSS send a stronger signal.

The VSS is a variable reluctance sensor.

For more information:
Variable reluctance sensor - Wikipedia, the free encyclopedia

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Ok...thanx

 

guess I'm gonna try a different PSOM....how hard are they to get out....I can get one for about 25 bucks....can't hurt...don't know what to check

 

The hard part is taking the cluster out.

Back of cluster:


PSOM still screwed on Speedometer:


Speedometer with PSOM removed:


The PSOM:

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thanx sub...sounds like I'm gonna have fun....lol

 

ok used a different PSOM.....nothing changed.....is there only certain years or models that will work?

 

I have heard that they made some improvements in 1994 to the PSOM but other than that all years should work.

If it shifts fine with the RABS module unplugged and not with it plugged in would say you have week voltage coming from the VSS.

If the speedometer head still does not work with the RABS module unplugged and it shifting fine you may also have a bad speedometer head.

You may also need to try another PSOM, maybe that one was also bad. Some posters say they get three or four at a time from a salvage yard to make sure they get a good one.

 

Guess ill take this one back....he said i could return it...and look for a different one....thanx again

 

Did you ever check to see how much the voltage was at 30 MPH?

 

Havent got a clue on how to do that

 

Did you read post #14 above in this thread?

 

btw...I found out that the easiest way to get the cluster out is loosen the four column bolts and removing the front 2....Getting the cluster out is easy then......just saying....lol

 

sorry for sounding dumb sub......but you're talking about the plug that goes into the PSOM? and do I just guess at what speed I'm going?

 

No the RABS plug C143 is at the drivers fender, do not use the EEC Self-Test plug.
You may also get to this wire under the dash on the passenger side but you would have to unplug the RABS module. Diagram below photo.

I have no idea how to find out if your ring gear is turning at 30 MPH. The information comes from the Ford shop manual and is posted below the diagram.









A8 CHECK SPEED INPUT SIGNAL


NOTE:
Only wiring harness end of connector is to be probed.

Connect an AC voltmeter to Pin 4 (speed in +) and Pin 5 (speed in -).

Does the voltage increase smoothly and continuously from 0 to approximately 3.5 volts as vehicle speed increases from 0 to 30 mph?

OR,

If available, a frequency counter may be connected to Pin 4 (speed in +) and Pin 5 (speed in -).

Does the displayed frequency of the signal increase smoothly and continuously from 0 to approximately 667 Hz at approximately 30 mph?

OR,

If neither a voltmeter nor frequency counter is available, vehicle speed control may be used as a good indicator. If it works normally, then the speedometer module is at least receiving a speed input signal and the wiring and sensor can be assumed to be good.

Does the speed control work normally?

Yes
REPLACE the instrument cluster. REFER to «Section 13-01A» for instrument cluster ordering information.

No
SERVICE wiring. CHECK for open or shorted wiring. If no problems are found, REFER to «Section 06-09A» or «Section 06-09B».

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