george , based on experience one of two things can cause the tcc to cycle randomly
a bad fipl , i know you checekd the sweep but they also become what is called noisy
when the engine is operating and teh vibration affects the fipl output it will have a nosiy signal return and cause tcc cycling
i have also seen wiring break inside the insulation and cause your concern from the fipl to the pcm
but since it stays on while slowing to a stop could also be the result of a bad psom
programmable speedometer and odometer it could be reading road speed that is incorrect and continuing to apply the tcc
personally i would start with a new fipl , this is of course if there are no codes presnt in the system but there will be for the tcc system since you wired in the toggle switch
removed it and clear the codes drive it until the problem occurs over 5 different times
it must have at least 5 failure cycles before a code will be stored
after that if no codes are present replace the fipl , after that you should cut the wires at the fipl and the pcm close to them and install three new wires in their place and try the system again
but if you can get a code post it so i know what it is before replacing any parts

 

the brake light switch has no effect on the transmission shift strategy it will only cause the tcc to unlock when there is power on the brake light circuit
i would definitely disconnect the brake controller since it has the led on it could be back feeding the brake circuit
as far as the transmission downshifting when releasing the throttle i would start with a fipl
you can get a clean sweep using a meter but it can be noisy when the engine is running
you would have to have a DVOM with a very high sampling rate to catch it
a analog meter works at a snails pace and will never see it

 

Well considering what you said and the fact that ic cleras up for a bit when I pull the conector from the FIPLS And that at some point the wires had been pierced by some brainiac testing the sensor. I think the wires are the problem. Also whan i was messing around in there I noticed one wire where it had been pierced looked like only a couple strands were still together I belive thats the problem.

High road speed signal will keep the TCC on? I thought that it would sut off from the drop in signal from the FIPLS when I let off the pedal. If it were the psom would the speedo be off as well? Or could it just be on the output to the PCM?

 

Well That didn't fix it I guess the next step would be the FIPLS?

I also noticed some times the torque converter comes on at 30 mph shouldn't it not come on untill 35? Can a noisy FIPLS cuase the signal to be higer than normal as well? Occasionaly it wount shift untill 2500-3000 on moderate throtle and also doesn't a reading of full throtle lock up the TCC?

Is there a way to check for codes without an anolog meter? or other expensive device? I have very litle money and realy can't aford to just start replacing parts or buy new tools.

 

try autozone they perform free scans but the throttle must be held wide open before the test is started or it will give a false code for the fipl
this only applies to idi,s
the fipl can cause delayed or early shifting depending on signal voltage
the torque converter should release when the fipl returns to idle but if the fipl reading to th eprocessor is still high enough the pcm thinks it is still at a cruise condition and maintain application , and the torque converter should lock at wide open throttle and again this will not occur if the signal voltage is too low

 

I just have to pull the battery cables for a bit to clear the codes right?

Also will autozone have the stuff for the EEC conector or is there an ODB1 conector under the dash that I'm overlooking?

Thanks for all the help.

 

Your OBD1 Connector should be located next to your windshield washer tank on your left fender. Make sure you connect both the main plug as well as the ground plug.

Note for some reason a lot of the aftermarket scanners will tell you that they are only good for the trucks up to 93', not including 94' as 94' was the transition year to the OBD2; however is you have an IDI then you should be able to still use the OBD1 scanner.

Seb...

 

do not disconnect the batteries
your vehicle has EEC IV , or as some call it OBD 1
any scanner capable of connecting to the connector can test it

 

Ok but you said to clear the codes then drive it until it acts up 5 times so how do I clear the codes?

 

I was plauged with my TC unlocking and locking again for several years at random times. We would disconnect the batteries to reset the trans. brain and no problem for a while. It was in and out of trans shops and Ford shops, but same old problem. I talked with another trans man and he told me about the connection between TC, brakes and CRUISE CONTROL. When you touch the brake pedal to disengage the cruise it will unlock the TC because usually you are stopping!.So any loose connection or other problem with the brakes can cause the TC to un-lock and lock. I never found out WHAT was wrong so I took the easy way out and swapped to a ZF5, so good luck

 

have you had a scan done and retrieved any codes

 

Not yet I've got bigger fish to fry at the moment, motor locks up when parked over night and pushes coolant ou the exaust.

 

ouch!!!!!!

 

yup hopping its just the valley pan gasket not a crack above a valve. Absolutely no compresion in the coolant.

 

I figured out my TC problem. I'm DUMB DUMB DUMB DUMB I got a new engine in it had to replace both batteries and now irs fine. well My left battery had a shorted cell so I pull the ground off it to isolate it well when I put the engine in i noticed that is where the grounds for just about veryting comes from yes it went to the block but that wasn't a clean ground. I feel smart.