94 bronco, transmission, converter issue
 

Its either the tranny or the converter. Is there a way to test them? I am leaning towards the converter because the bronco and tranny do fine until it is warm then slips.

The fluid is clean and maybe 1/2 qt over full currently.

Some days it never acts up, other days it acts up in 8 miles or more. It does fine when i use it as a 3 speed, locked in first-2-3...OD is the biggest issue, will be going fine then rev like i hit neutral. At its worst, from a stop in OD and I mash the gas, it shifts fine (maybe a touch firm) 1-2-3...its the easy driving where it touches neutral then bangs into gear.

No codes thrown.

Whats next test? toss in a new conveter or tranny shop?

Here is my story on that...https://www.ford-trucks.com/forums/9...lp-please.html

Could be MLPS or VSS but in my case it was the PCM

what size tires are on the bronco at the moment? how did you pull codes?

I got the codes the same way everyone else does, by counting blinking engine light...bronco is running on 35s currently.

so have you programed the PSOM for that size tire? This is extremely important since the tone ring provides engine speed etc.. and with the larger diam tires this figure gets thrown off causing the tranny to not shift properly etc..

thats great you can count. LOL

I second everything Kem said.
Calibrate your speedometer if you are not travelling a mile per road signs every sixty seconds travelling exactly 60mph.

Codes...you are aware that KOEO shows first, twice...then a spacer followed by CM (continuous memory codes) twice? The CM will give you a hint about your transmission issues.

While checking codes, correct engine problems first. The E4OD transmission is not happy unless the engine is.

tires have been on for 15 months already. aside from one jeep, I have never reprogrammed a truck speedo because I went with a larger tire. that is not saying I have been right to do it that way. My excursion has 37s and has not been recalculated either and have had no issues with it.

Is there an easy way to re-program the speedo?

It is time for me to step aside. My best suggestions were my story and to calibrate you speedometer get CM codes.

reprogramming the speedo should always be done Period. do a search on here on how to program the PSOM. ive seen some decent rights on here and also over on fsb.

This is a grade school response that doesnt help the issue.

I found a ton of info on the PSOM programming. Turns out it was very simple and now the speedometer is nearly exact-thanks for pointing me in the right direction. Cannot believe how easy it was, and that it is not as easy on newer vehicles.

After the test drive, I attempted to pull codes again. The last time when I said it was clean, i could have said I got only 2 codes; 111 and 539 I think which is because the AC was on. This time I pulled codes and got one from the past 628 (converter clutch lock up) which is why I thought that the converter needs replacement. I also got 452 (Computer detected an error in the VSS or PSOM signal during the last 80 warm-up cycles). Would I get 452 from reprogramming the PSOM? I disconnected the battery and will drive it again tomorrow for a while and pull codes after to see if I get the same 2 or something different again.

The more I read on this, often dealerships are blaming the ABS for the VSS code and often it is not the ABS. My ABS light is on becasue the front sensors are disconnected. I do not intend on replacing them either. They have been off since the tires were installed and the front end was rebuilt.

Any ideas?

Congratulation on your progress. We will be waiting for your KOEO and CM codes and give you the best answer we can.

having those sensors missing up front probably isnt helping. if the codes dont change after your next test i would suggest going to a wrecking yard perhaps and getting those sensors.

drove about 50 miles today. acted up once. pulled codes and only got the 452 code for vss/psom.

if the front sensors could be the issue, why did it not act up immediately? it worked perfectly for almost 7000 miles since the front rebuild.

I can get the front sensors for about $35 each, easier than attemptign the junk yard. the rear VSS is about $25 or so.

Does the brand matter? Dorman? Bosch? ACD? I did not find a motorcraft part for these. What would you do next? VSS? front sensor? cruise works fine, no other issues so I am not thinking it is the PSOM. Maybe the MPLS or MLPS whichver is on the tranny...if the front sensors fix it, I will haved mixed emotions as I removed them myself and it did not screw anything up quickly. the sensors were trashed as I removed them from the hubs as they were not removable without damage...so into the trash they went.

I would start with a Motorcraft VSS. O'Reilys sells Motorcraft. Removing the old one and cleaning the tip may cure it but I would replace it while you have it out. Clean and dielectric grease the connector of course.

Disconnect the battery while you do it then after about 20-30 minutes of driving pull KOEO and CM codes.

the vss is also known as the rear abs sensor. sometimes the parts store will get confused and sell you the incorrect part if you call it vss.


the ABS system is tied into to so much that it wouldnt suprise me if this takes care of the rest of your issues. I would start with the front abs sensors and just clean off the rear sensor.