1994 Econoline Speed Sensor
I have a 1994 Ford E-150 Econoline 5.0L that has very persistend problems with the infamous bouncing speedometer. I have replaced the tone ring, replaced the speed sensor, replaced the PSOM with another one from the junkyard etc. What eventually fixed the problem was sending the PSOM to Module Mechanics. They fixed the board and the speedometer was working fine after that. 2 years later though the bouncing started again. I resent it to Module Mechanics and they replaced it with a replacement unit within the warranty. This replacement unit however has even more problems; it bounces at 60 mph, and does nothing below 20. I have contacted them and they advised me to check tone ring, wiring and speed sensor. They also noted that it might not work correctly with an aftermarket speed sensor. I do have an aftermarket speed sensor, so i am planning to replace that. After checking rockauto have found 13 different speed sensors that fit the vehicle. 12 aftermarket (i think) which cost around 10 dollar, and one original sensor that costs a whopping 144 dollar (!!!!!)
My question is: does anyone have experience with the aftermarket sensors, and maybe can advise me with this?
That does not mean it cannot happen
I sure would be running some VSS pids from a NGS
Difficult if not impossible for a layman or novice without thousands in special tools
The connector at the RABS sensor wires used to break and cause intermittent connection
Who made the RABS sensor?
You have a new Ford one in there I take it?
It's time for an ohmmeter and a EVTM with a schematic, so you can test the wires back and forth from the cluster and ABS module to the speed sensor
Good luck
Do you have an EVTM for it?
You need a Ford service manual or the pages printed from AllData for the speed control surging complaint flow chart
That's where I would start on your problem
3 fat books, several hours and a NGS (and a few beers or shots of good whisky)
The cheapest one that works (your RABS valve)
These are EVTMs
A ton of valuable info in them, from switch testing to component locations to splice and ground locations
The "how the system works pages: is how I got schooled over the years
You have to be smart enough to go to school before they'll send you
The NGS is the new generation star (Fords tester for your year of van)
PIDS are parameter identification data
For instance, there is a VSS pid (vehicle speed sensor) that will read 30 on the NGS screen when you are going 30 mph down the road if the computer sees it
That is the advantage of the NGS
Long before we had NGS or PIDS we were figuring these things out
Just takes longer and you have to be smarter
We used to have guys cheat and unhook their odo and keep the speed control and trans shifting
They were mousing warranty on their new trucks, where they could have a ton of miles on the truck and not leave warranty until the time expired
I asked my cheating co worker what he did, he only said it was absolute hell finding that exact wire that needed to be cut
That is the wire you need to trace down on your van for the speed control issue
I would run through the speed control flowchart (in a 1994 Ford Econoline service manual) (body chassis electrical) and get into some pinpoint tests that way









