Odd Trans Shifting

VintageIronFab · Post by **VintageIronFab** » Mon Oct 03, 2016 6:58 pm

Hello All,
On my 96 Bronco -- I put a new TPS sensor in and it still happens-- as the engine revs at 3/4 to full throttle -the trans won't shift until you let off the gas then it shifts fine. The CEL is on btw. Doesn't seem transmission but sensor related, maybe a TPS tune or MLPS related?? Just hate the thought of taking it to a shop and it be dished a transmission issue when it's not.

Cactus Cooler · Post by **Cactus Cooler** » Mon Oct 03, 2016 10:25 pm

Not sure if it is related because of the difference in years ( mine is a 90 e4od) was having the same issue. Long story short, it was the drive gear on the end of the cable that went from my speedo to the transfer case.( yours, assuming its a digital deal, mine is an actual gear deal) replaced the gear on the end that went into the transfer case on the cable ( again still a sensor that sends a signal to shift ) apparently gear is stripped ( plastic ), it worked for a bit then started doing it again, the gear that is in the transfer case is also stripped ( transfer case needs coming apart to repair apparently)...... so I unplugged the sensor, works now and gets the best mileage ever

Tchajagos · Post by **Tchajagos** » Tue Oct 04, 2016 12:25 am

Any codes? 96 is OBDII so it should be easy to pull codes. I believe that when the throttle is open 3/4+ it tells the trans to up the line pressure for a more firm shift. Don't quote me on that. I think I remember reading it somewhere.

http://www.ford-trucks.com/forums/90445 ... found.html

funinthesun95 · Post by **funinthesun95** » Tue Oct 04, 2016 5:06 pm

art carr shifter or stock?

VintageIronFab · Post by **VintageIronFab** » Tue Oct 04, 2016 7:55 pm

It's all stock

funinthesun95 · Post by **funinthesun95** » Wed Oct 05, 2016 9:07 am

ok next question would be is the trans original or swap?

if original valve body changed or anything?

VintageIronFab · Post by **VintageIronFab** » Wed Oct 05, 2016 4:25 pm

All stock

Tchajagos · Post by **Tchajagos** » Wed Oct 05, 2016 5:11 pm

Any codes?

hollandermotorsports · Thu Oct 06, 2016 8:33 am

This will sound crazy but the VSS in the rearend housing caused the same issue in my 7.3l diesel. Have you checked that? You still have the original 8.8 in it? A lot of time they will not shift correctly if they do not see the pulse from the VSS.

hollandermotorsports · Thu Oct 06, 2016 8:35 am

Also my 97 7.3l did not throw any codes due to the fact it did not know there was an issue. We found it by driving around hooked up to a buddy of mines computer watching for different signals after we swapped a valve body in it. it was literally a cut wire for the VSS I butt connected it and it has not skipped a beat since.

panabax · Post by **panabax** » Thu Oct 06, 2016 1:16 pm

Did you get a motorcraft or generic parts store TPS? I would start by checking the voltage on the TPS. At closed throttle it should read about 1 volt and at full throttle it should read 5 volts. It the voltage is not right, the eec won't know where the throttle really is. Is your speedo reading correctly? The '96 eecv uses a combo of vehicle sped, rpm and throttle position to determine when to downshift. If it is not downshifting correctly, I would suspect one of these sensors before I would suspect thetranny itself. As others have mentioned, the VSS could also be the culprit. How does your soeedo read? Does it jump around?

Also, definitely pull the codes. The eecv controls the shifting and if it is throwing a code it could effect the shift strategy it uses.

Baxter

damon1272 · Post by **damon1272** » Sun Oct 16, 2016 8:03 pm

It most likely is your VSS. Changed out many with this same condition. Cheapest fix for your shifting problems.

VintageIronFab · Post by **VintageIronFab** » Fri Dec 02, 2016 6:12 pm

Well I guess the trans shop replaced my TPS sensor and fixed the wiring (which I'm sure isn't a proper repair but who knows) and now the computer can see the TPS signal. He said one of the solenoids in the trans is bad he thinks. I guess the fluid is kinda dark - so he's gonna drop the pan and look in there for junk and if it looks ok the solenoid that's supposedly not operating properly. Any thoughts from the gallery??

VintageIronFab · Post by **VintageIronFab** » Tue Dec 27, 2016 1:48 am

Turns out that after 6 months and 2 idiot shops (1 of them being a transmission shop), I got ahold of a guy (thx Ryan White) and 1 hour later a confirmation. Zero trans issue - the plug going into the firewall for the computer is bad. The little tangs that hold the plug securely into the computer have some which are bad. So I need to source out a new plug or used one and swap all the wires out. Everything is fine at the moment but at least I'm giddy with the fact no need for a transmission!!!

toddz69 · Post by **toddz69** » Tue Dec 27, 2016 3:01 am

VintageIronFab wrote:Turns out that after 6 months and 2 idiot shops (1 of them being a transmission shop), I got ahold of a guy (thx Ryan White) and 1 hour later a confirmation. Zero trans issue - the plug going into the firewall for the computer is bad. The little tangs that hold the plug securely into the computer have some which are bad. So I need to source out a new plug or used one and swap all the wires out. Everything is fine at the moment but at least I'm giddy with the fact no need for a transmission!!!

Firewall side or engine compartment side?

Todd Z.

RyanDS650X · Post by **RyanDS650X** » Tue Dec 27, 2016 7:56 am

No worries Matt, glad to help.