4.00 volts in park/sitting still.
3.78 volts in reverse
2.86-2.90 volts from 1st-2nd shift (under normal acceleration)
2.86-2.90 volts from 2nd to 3rd shift (under normal acceleration)
1.90-2.00 volts when I revved the engine to almost 4500 1st to 2nd (shift felt like a rear end).

I managed to get a quick resistance measurement from the EPC solenoid, which came to be 4.5 ohms (cold today so I went quickly). That is within spec from what I read. I figure since we have the resistance and the voltage, you can calculate the current, unless more precise values are needed.

I'm not sure if these values are actually right because I can't find any information online saying if it is bad, but from what I can tell, it's at least working, and the current value goes down as the truck revs harder. The only thing I can think of now is wiring from the VSS.

I would like to add that when the values for voltage changed, they would gradually get lower, and then instantly spike. For example, if I reved the engine to where the voltage was 1.90-2.00 volts, the second it shifted, it would spike all the way to 3.78 volts (not gradually at all). This is a similar symptom the transmission shop noticed when they described that there was a "spike" in a square sin wave coming from the computer, where they identified it to be the TPS, but they were not certain. If I'm correct, the voltage should not spike but should gradually move back to 3.78 volts (quickly but not instantly).

 

So I tried again with measuring everything, except it seems my multi-meter does not have the ability to do current. So I watched the values again, and the numbers seem to go down as its just about to shift. I had a few good shifts around 3.00 volts, bad one at around 4 volts, and a bad one around 2 volts. The normal cruising voltage was around 4.7-4.9 volts. My second resistance measurement came to be 6.0 ohms, which is still within spec.

I did a check using the RABS plug to see the resistance from the VSS. I first measured the actual VSS, which gave me a resistance value of 1995 ohms, and then I measured the plug value, which gave me a value of 1887 ohms. I'm not sure if that reasonable, but it seems so. I also measured the volts AC that came off the VSS while driving (using that RABS plug), and it gradually moved from around 0 to 3.5 volts, and continued to rise depending on the speed. It hit 3.5 volts around 30 mph (within spec from what I'm told).

I tried to retrieve codes from the RABS module using the ground connector, but for some reason, no codes would display on the ABS light. I also tried to figure out the VSS wiring that went to the RABS module, but I couldn't figure out which wires they were.

As for the "winding up transmission" issue. It seems that when my truck is about to shift hard, it does wind up very high. There is a particular point when its winding up (just before its about to shift) that adding throttle only seems to make it wind up harder and shift tremendously hard. Only way to stop the bang is to let off the gas quickly.

I did find this peculiar, but if I manually select 1st gear from the shifter and allow my truck to move forward till my desired rpm to shift, then select second or drive, the truck does not hard shift, or bang. Under normal acceleration, the shift cannot be felt, but under high rev (same hold in first, manually move to 2nd) it feels like your thrown forward a little bit, but there is no bang, no hard shift, etc.


My questions are if someone would know how to retrieve the codes from the RABS module. I would like to see whats stored, but the methods online don't seem to work for me.
My other question is what can I do now to track this problem down (excluding codes from the RABS module).

 

This sounds more like a TPS issue to me.

 

I have tested the new TPS by hand with a multimeter, and saw a steady increase with voltage, with no spikes that I can recall. It sat around 0.90 volts closed and maxed around 4.5. Aside from that, all I can think of is wiring, but I don't see how wiring could result in this issue. Otherwise, I'll stick my multi-meter again on it tomorrow and try again.

 

I don't know if this will help but for engagements, I began to shift back and forward between drive and reverse (not immediately, but every time the RPM settled, I'd shift back to drive or reverse). Reverse was kinda hard going in, it just felt like the truck moved backwards immediately, as if the truck moved back a bit and dropped in height an inch or two. The gurgling sounds usually only starts happening after I've gone in reverse, or have sat a while.

Anyway, after a few times, reverse got a bit harder, and drive got softer (was not lurching forward anymore), but I could hear a sound as if 2 pieces of metal were hitting each other when ever I went into drive (not reverse at all). On some occasions when shifting into reverse, its almost as if the motor is ready to stall. I had a drop 3 times that were at 500 rpm just after shifting to reverse, and then the engine kicked back up to a safe idle area. I've had this before but I never really noticed the issue till now.

 

A few trucks ago i had one with the hard shift... after changing everything and anything it was the computer. Couldn't see nothing out of the ordinary but sent it away and came back to perfect truck.

 

I thought the same thing a few months ago, but the new computer we already threw in didn't change anything, and the old one had a completely burnt off leg on one of the capacitors.

 

Hmmm.... well throw my thought out the window! And you got the PSOM checked out too is that right? These trannys drive me insane when they don't work... my last issue i thought the thing was slipping, and hard shifts, highway revs everything and it was my third brake light

 

So its been almost a month since my last post, and I have been having problems with the truck since the weather got warm. My truck is now beginning its phase again into stalling in reverse when backing up a hill. This happens under moderate gas in reverse, and the only way to stop it from stalling out is by pushing down a lot. The truck is still having its 1-2 hard shift problems, and 3rd gear is having its strange issues with not feeling like its engaging all the way. The truck under very low gas is now throwing ABS lights at me (this all happens when it hits around 70+ degrees outside).

Today I checked the codes with the truck on and off. As before, the KOER test produced 225 on the 2nd try, but 111 on the first try. The KOEO test produced new results into the problem. On the first test, I got code 622 (which is not a continuous memory code). Code 622 is Shift Solenoid #2 circuit fault. This code went away after the first try, and did not come back at all. One code is completely stationary, and that is code 626. This code read continuously for 5 separate tests, and this code is the Coast Clutch solenoid circuit fault.

Code 622 seems to relate to my problems, but its strange why it went away after one test. The coast clutch solenoid issue might also lead to something going on.

 

It sounds to me that you likely have a wiring fault to your transmission. Possibly a bad solenoid pack connector.

 

The entire transmission wiring harness was taken apart, and a new connector was put on it. There should be no issues with the wiring at least from the solenoid pack connector to the connector just below the fuse box connected to the wheel well. The solenoid side of the connector however, was not changed, and as far as I know, the pack is brand new (cannot confirm nor deny).

 

Well, you appear to have an intermittent connection problem somewhere then.

 

This was probably a simple problem to start with but after all the work that has done I suspect that there are more problems now than when you started.

The MLPS problem was used to scam countless truck owners. This might still be a problem for you. I have seen several that were pinned backwards. There are many different wiring diagrams for this plug. You can't trust which one is right, test it.

Do you have the EVTM? ATSG manual?

I don't know how good this thread is but it has a lot of information:

https://www.ford-trucks.com/forums/9...d-i-found.html

Do your reverse lights work?

 

We were having this same problem before the MLPS was changed. The one that was originally in there was the original one, and the new one was repined exactly as the old one into the new connector. From what I read, I'm not sure if that's correct or not, but some websites say the pinning is the same, or 1 and 4 are swapped. Drivability did not change after the swap, so I assume everything is alright.

My reverse lights do work. Strange thing was when I put it in reverse the first time from park to reverse, my dad did not see any lights. When I went to drive then back to reverse, they all came on. Park to reverse then had them come on. Quite strange, but I don't know what could cause that.

As for some of my symptoms that I described before that may not have been clear, its definitely the transmission slipping. I mainly addressed the problem when I would go from a stationary stop slightly up an incline. The truck would rev up, barely move for a sec then shoot off after a nice little hit. I had to look up the symptoms, and they say little clunks changing gears or strange gear shifts are all symptoms of a slipping transmission, and I believe that to be the case. The 1-2 shift could even be because of the trans slipping, and so its raising line pressure to prevent it (can't be sure on that last statement). What ever is causing the slip, it's in all gears.

Code 626 (Coast Clutch solenoid circuit fault) still remains after 10-15 tests, without going away and coming back, so there is definitely an issue with this solenoid, but the only thing I can think of now is the solenoid is fried or something inside the transmission itself is causing problems, because all the wiring checked out from the transmission side to the connector just below the fuse box.

 

If all the wiring checked out between the PCM connector and the transmission connector (good continuity, etc..) then either the PCM is bad or the solenoid pack is bad.