Ford F150 Vehicle Speed Sensor

[Tom]

I have a late model F150 and have recently been experiencing (INTERMITTENT!)
problems with the vehicle speed sensor (or related sensor/system). When
I reach speeds around 35 to 70 mph, the speedometer fluctuates rapidly in a
range of about 20 mph on either side of the "true" speed.

When the speedometer is fluctuating, the transmission may slip (exit lock-up)
and shift gears. Cruise control will not hold during this phenomenon. I
viewed the vehicle speed signal coming from the ECM via scan tool and noted
that this signal is also fluctuating when the speedometer is fluctuating.

The problem started at approximately 20k miles and will occur about 1 out of
every 5 drive cycles.

I am interested in hearing from someone who has or is experiencing a similar
problem with Ford's vehicle speed sensing system. Thanks for your input.

~Thomas

[Chevy]

have you tried lubricating the Speedo cable ,

"Tom" <tom_...@hotmail.com> wrote in message
news:80a3896f.01061...@posting.google.com...

[Sam Spade]

I just fixed this on my 95 Bronco, the Speedo started rapidly
flutuating and then finally went kaput and stayed at 0. The auto trans
was greatly influenced by this.

Very easy for me to fix, amazingly the VSS was only about $10 from my
local crooks in dealer parts. It should be mounted on top of the rear
axle, has a 2 prong connector.

The problem has not returned after 3 months of use.

SS

[Sam Spade]

On Tue, 12 Jun 2001 04:04:22 GMT, "Chevy" <chev...@home.com> wrote:

>have you tried lubricating the Speedo cable ,

This vehicle may not have a speedo cable, on at least some of the
newer fords the ECU uses the output from the ABS rear wheel speed
sensor to display road speed.