Electronic Transmission Issue - Any input helps!

Layla11242

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Southington, CT
Hi everyone, I'm getting a little desperate as I'm $2k into my issue with it only getting worse, so I am seriously considering selling the vehicle. I've looked at every transmission related forum on here and I cannot find anyone who solved this issue. Any discussion of this usually gets derailed into something else not relevant. So please bear with me before just saying "replace the valve body and servo bores", thank you. The vehicle is a 2003 Lincoln LS V8

TLDR: My shifting issues keep dramatically changing every time I repair/ replace the PCM. Transmission shop can't figure out why but recommended the next step would be to replace the solenoid pack for $850. The issue with me believing that is that I just replaced the solenoid pack and had the entire transmission rebuilt 20k miles ago.

Issue: My issue started with a harsh shift into 4th gear while the car was warm, a flare into 4th if cold. So, I sent the PCM to SIA electronics as I read in this forum.

When I got the PCM back, the car went into failsafe mode. So, I shut it off and then tried to turn it back on and it wouldn't start. I then found out that my battery was leaking (the battery was only 2 years old but was already a year old when I got it for some reason.) I replaced the battery, and the car started right up. Now the car doesn't have the issue with 4th gear (except for occasional slip) but will randomly downshift really rough. It feels like the car tries to engage twice and it only happens about 1/10 times the car downshifts from 4th to 1st. After this bad downshift occurs, the transmission starts to have other issues. Reverse will drag the transmission and engage and disengage over and over. There are other dragging/ double engagement issues that sometimes will occur, and if I drive around long enough, I eventually lose 4th gear. All issues reset after turning the vehicle off and waiting some time. Issues start again after the 1/10 bad downshift occurs.

I had the PCM reflashed at a dealer and it had no effect.

Sent the PCM back to SIA and the transmission was insanely erratic once I put it back in (would drag in and out of gear while driving at a consistent 25mph), but only for the first drive. After that it acted the same as when I first got the PCM repaired.

So I figured if repairing the PCM changed the issue, I should replace the PCM. I bought a new PCM from Flagship 1, made sure the part number matched up. After putting in that PCM, The reverse and downshift issues are gone entirely, now all my issues are with upshifting. 1-2 jumps into gear, 2-3 slams so rough into gear then deaccelerates for a second, 3-4 "drags the clutch" and slows the car down as if I'm engine braking, 4-5 is rough but not half as bad as 2-3.

Why does my issue keep changing every time I do something to the PCM? I have no CEL, transmission was just rebuilt 20k miles ago, fluid is clean and at level. The tranny shop said it's 50/50 on either the PCM or solenoid pack, but he can't tell which, and because we had just replaced the PCM he is betting on the solenoid pack. I'm really having a hard time believing it though since everything in the tranny was replaced/rebuilt 20k miles ago. Can solenoids really fail that quick? Are there any other electronic parts or areas I should look for before spending the $850? As I mentioned before, I've already put way too much $ into this and I'm very tempted to sell the car. Any input helps :)

Thank you
 
I'd like to add that the car is finally getting codes and an occasional "check transmission message". Still doing some research but I figured I'd put the codes here in case someone knows the answer already or if someone happens to need this forum in the future.

P0963 and P0748

Thanks
 
Hi Guy, when i had my 04 LS repaired in Anniston Al Aamco, the elder Robert told me the 03 LS was a unique year for the transmission control. I would also would talk to Pat Garrett at Level 10 transmission about this issue. Jim at Bob Allen Ford has rebuilt ABS units and pcm also.(913)3812999. I hope this helps.
 
Mine has been doing the same thing. I cannot figure it out for the life of me either. I wish someone has been through this that could help us.
 
I'll be working on it this weekend. Based on my conversations with my tranny shop and Flagship One, as well as my own research, we think it's either the wiring to the solenoid, or the solenoid pack itself. Thankfully I have the codes now but I'm still stunned by how long it took for them to show up. I'll post back here with what I find.
 

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