A poor VSS signal appears to be responsible for some erratic behavior (late & harsh upshifts) of the E4OD transmission on my 94 Bronco. The problem is intermittent with the vehicle performing well at other times. Occasionally I also get very sluggish acceleration from a standstill with the vehicle acting as if it is in too high a gear.
I have had both the MLP and VSS sensor replaced and I am still receiving poor VSS signal code. A Ford dealership has had the vehicle for a few days now and they have identified the problem as being a bad ABS module. They are telling me the signal routing is Sensor to ABS to PSOM to PCM and then transmission. Therefore it would appear a bad ABS module could lead to a bad signal being sent to the transmission.
They are telling me a new ABS module is around $1000 therefore I am keen to know whether what they are telling me is correct. Any comments?

 

What year? For their description to be true, it must be '93-96, but I'd like to know for sure.

You should be able to get a junkyard module for MUCH less.

 

It's a 1994, 5.0L (I've had it about 18 months). I guess I'm surprised that I could have a bad ABS module giving a bad VSS and not see any indication of it either by the ABS light coming on or noticing something wrong with the speedometer/odometer. I had read several threads discussing bad PSOMs but when I questioned the dearlership about their diagnostics they assured me they had nailed it down to the ABS and not the PSOM. Anyway, they are in the process of replacing it now....but you're right at those sorts of charges I need to start getting parts from elsewhere.
Thanks

 

If it doesn't fix it, make them give you 100% refund and KEEP YOUR ORIGINAL parts no matter what happens.

 

had same problem on 95 . it wasnt the abs moduel it was the electronic moduel under dash .

 

I had the same problem in my 94 Van. The dealer said it was the Brain in the Speedometer that tells it when to shift and wanted $600.oo to replace it. They were right but I went to the junkyard and got a speedometer cluster for it for $50.oo and 90,000 miles later it is still working fine. LOL --Jerry in Indiana--

 

The ABS module has been replaced and guess what.....it didn't fix the problem! Can't say I'm too surprised from what I've read here and elsewhere. So it's back in the shop this morning and I told them (again) that maybe the problem is the speedometer module behind the dash and that maybe they should focus their attention on that.
Don't worry Steve - I kept the old part and will be requesting my $$$ back.
Thanks for all the feedback. This is a great forum.

 

Did you ever get the problem fixed? I am curious as to what the problem was.

Also what is the Electronic Module under the dash? and where is it.


Thanks,
Geoff

 

It's maybe too early to say if the problem is fixed but since I picked the vehicle up from the Ford dealership the other day it appears to be running well.
When I took it in this time they decided to replace the spark plugs, cable set and distributor cap and adjust the timing - they noticed the engine missing intermittently while test driving it (something I'd noticed before as an occasional shudder while idling at a stop). After testing the ignition system they said the wires were in bad shape and were causing an intermittent short.
I now no longer get the shudder and (touch wood) I am no longer getting the intermittent harsh up and down shifts nor am I getting a code 452 (bad VSS signal) anymore.
My guess is now that this short was causing interference with other electrical signals including the VSS signal??? Once I'm happy it is running properly I'll get back with the dealership to see if they can explain this.
When br0nc0 talks about the electric module under the dash I assume he means the PSOM - the programmable speedometer/odometer module. I haven't put my hands on this yet but I understand it's basically mounted to the back on the instrument cluster.

 

I don't know which module he meant, but the PSOM is the speedometer. It's inside the instrument cluster.

 

It was too early to say. The problem isn't fixed. It's back in the shop and I am waiting to hear back from them.

 

The part ford replaced on my truck was part #f4tz-2c219-a moduel asy-brk. This fixed my problem i had with my truck. The part was 312.37 dollars, They told me the abs moduel was bad in mine ,but it wasn't. I also bought one at a junk yard., but mine was good.

 

They've now replaced the PSOM - the part was around $350. So far it hasn't played up (touch wood) but I going to have to drive it around some more before I say for sure it's fixed.

 

I recently bought a 1991 E150 van. it was driven yearly but very little. Garage kept, under a cover. 21,000 actual miles to date. It drove like new for 300 miles or so and then I went on a 400 mile trip. Pouring down rain. The van worked fine for 350 or so miles then the transmission started shifting in and out of OD. pushing the OD off button on dash did not help. Seemed from a stop (in Drive) to shift from first to 3rd. manually 1st held up and down, same for 2nd. In drive it kept the 3rd-OD shifting back & forth. 1st garage, changed trans oil & filter (When pan dropped it looked like new, no sign of wear, slip, heat etc.) did not change anything. Took to Freedom Ford, Wise VA. they said it was shot & needed rebuilt?? we tested the speed sensor (rear Dif)it was OK. installed new manual lever position sensor, throttle position sensor. No change there either. Took to a Trans shop. they got a code for #2 shift selinoid, Installed the selinoid pack, code cleared, but not change in shifting. with the pan off again still no signd of wear, heat, slippage etc. Trans shop owner said drive it home and it should not ruin the trans.(but not to pull my motorcycle trailer, that I went after) drove 250-300 miles, still acting up. got tired, pulled off and took a nap, leaving the van running 20-30 minutes. took off and It shifted perfect OD off button worked too.about 100 miles. Stopped for gas and it started acting up again. Parked it for a few days. Started it up and let it idle 30 minutes or so. worked great for 25 miles of so and started acting up again. Please help.

 

Look up ECMTOGO.com and call them. True, if the engine is not running well it seriously affects the E4OD. For me, after, VSS, MLPS, two shift solenoid assemblies and completely removing the harness they fixed the shifting issues, intermittent dying, no starts for $195 plus shipping. It was the PCM. It only took six months to find it DIY and no shops. Runs like new at only 194K.