About a week ago my speed o meter started jumping around (at highway speeds) and abs kicked in during normal stopping(no abs light at this time). I read some of your postings and changed out the abs speed sensor hoping for a quick cheap fix but it didnt help. Now the abs light IS on, and when i brake hard the speedo will drop dramatically and then rise back up to correct speed. I havent drove it enough to see if the speedo still jumps becuse it mostly happend at highway speed with the original sensor but i can have more info tommorow. Please give any ideas that may help you seem to be pretty knowledgable about the abs speed sensor or vehicles speed sensor whatever you want to call it

 

I was reading your problem & figure on an observation until Paw Paw responds. Does the speedometer seem to make any noise when it jumps? That would probably be a dry speedo cable when it's cold enough, say 15 to 20 F.

 

Welcom to FTE.

Well I probably know just enough to be dangerous!!!! lol

Lets see, on your 98 Ranger you origonally had a acting out speed-o at highway speed & had the ABS actuating on a stop, but no ABS trouble light.

Then I'm given to understand that you've changed the rear differential ABS speed sensor, but it MAYBE didn't solve the speed-o problem & to boot you NOW have a ABS trouble light!!!!

So that might suggest that you may have more than one problem.

If the speed-o is still acting up, maybe it's a electrical contact problem with the speed sensors electrical connector contacts, like contact corrosion, or a wiring problem, like broken wire strands that are making intermittent contact under the insulation, or maybe damaged insulation thats causing shorting to the vehicle chassis, or maybe the new speed sensor is bad, you know, maybe "Murpheys Law" is messing with you.

Anyway, if you can get a scantool hooked up to the in cabin diagnostic port, that'll read the speed sensors PID input to the computer, to see if it's corrupt, that might help narrow down where the problem origonates.

Now if the speed-o isn't acting out with the new speed sensor, then you need to pull the ABS trouble codes & see what the system is unhappy with.

There are instructions on how to pull the ABS system codes in the "Tech Info" thread atop this forums thread listing page.

So do the road test & tell us if the speed-o is fixed & if not hook up the scantool & monitor the speed sensors PID input to the computer & let us know how it looks, then pull & post ALL the ABS trouble code numbers & we'll all take a shot at a diagnosis.

 

Yesterday after i replaced the ABS speed sensor the ABS light turned on, it had never been on before with the previous sensor, and this morning when i drove it it was off.

So I took it to the shop and they said it may be a bad speed sensor that i purchased from oreilly. They reccomended taking it back and buying one from ford to see if thats the problem with the speedo.They also said it may be a bad "head" in the dash. I'm gonna try the new sensor to try to fix the speedo problem.

Then on the abs (2 wheel ABS) they grounded out a wire under the passenger kick panel and it made the abs light flash 16 times which i guess the code says there is nothing wrong with it, but something weird is still going on. The pedal stay vibrates, clicks or whatever under normal stopping. They also checked a Constant On Memory fuse I think is what it was and its ok. So I guess i'll have to drive it until a light comes on becuse they could pull no code even with the live mode scan tool. Unless the new speed sensor somehow fixes it.

Please continue to reply with any info or suggestions you may have!!

 

Hey Matt2.9stx
There is no noise in the speedo cable that i can hear and its been down to 4 degrees. But thanks for the response and any more are welcome!! So you have a dually ranger I'd like to see some pics if you have any!

 

Full duals refers to the exhaust pipes. Sorry. Not a fan of dually pickups. Wonder how low the gearing would be. Yikes! Have a cousin who rented a dually Toyota Uhaul truck with a V6. THAT thing was a dog! So I'd think a good dually should have at least a 302 Windsor V8. Or a diesel. Saw a nice dually full-size at a local dealer yesterday while driving my dad around. Diesel, banged up ex-farm truck with some rust, but could be fun. No transfer case though. So I wonder if that's still 4 wheel drive.

 

OK, so this morning the ABS trouble light is off, but the speed-o is still acting out????

Did the shop drive the vehicle, or jack the rear wheels off the ground & spin them up to the trouble speed, with the scantool hooked up, so they could monitor the speed sensors PID output to the computer????

BTW, your model Rangers speed-o is electrically driven using inputs from the rear ABS speed sensor.

The tranny, cruise control & ABS system also use the speed sensors output to do their thing, so if your having cruise control, or if you have a auto tranny & are having shifting problems, maybe they're also clues that the rear ABS speed sensors signal is corrupt for any of the above list of things, so check the wiring, connector for bent, damaged, loose , or corroded pins or sockets, skinned insulation, or broken wire strands, or salty water in the connector & if all that checks out, then suspect the new speed sensor is bad.

Let us know what you find.

 

So I took your advice and traced back the wires leading off the speed sensor and about 2 feet in I found a spot where the plastic conduit had broke. The 2 wires were rubbing together causing the insulation to wear through!! I'm guessing that wind was causing the bare copper to come in contact hence the speedo problem at highway speed. Anyway I cut the wires and connected them with butt spices, wrapped them tightly with Super 33, and finished it off with heat shrink that I had left over from an underground splice kit. I hope to not have anymore problems with it but if I do I'll know it's not the speed sensor becuse I just replaced 1 that probably wasn't even broke. I appreciate all replies to my post especially Paw Paw's THIS WEB SITE IS AWESOME!! I'm not much of a mechanic but my day job is residential/light commercial electrician so if anyone has any ?'s on that matter feel free to email them to jekstrom86@live.com THANKS

 

OK, good trouble shooting & feedback & to hear you got it put right & are "on the road again"!!!!