Typical scanner will tell you nothing at all about the trans (except OBD-mandated P0 codes). IDS will let you see TFT (TOT) etc. Some other costly tools also can (AutoEnginuity, wow so expensive, iCarsoft may and is also pricey).

 

Well guys here's a quick update.
Rechecked fluid levels today. Temps where between 35-38C.
It seemed to be full had a stream dripping out the whole time. Still have the same jerking at idle while cold. 😞

 

Suspects include:
1. engine fault (upsets trans) such as an air leak
2. torque converter?
3. er, ideas?

 

Well guys, I have great new to report!
The car finally gave up some codes last week.
1. P0400 EGR Fault
2. P0306 Cylinder 6 misfire
3. P1643 ECM to TCM Can Fault
The EGR fault I had since November prior to tranny issues. I replaced the valley hose then managed to break the Egr or its leaking.
I replaced all plugs and #6 coil yesterday. Drove around yesterday and today no issues.
No more jerking in and out of Drive, no more slip, no more squawk. I guess the tranny was getting confused from what was receiving from the engine.
Thanks for all for the support!

 

So was it most likely the coil all along?

 

Sounds like it.

 

Yup, and/or plugs as well. I don't believe they were ever replaced.

 

Great. This was as i suspected back on post #6. These very intermittant issues are typical.
Much cheaper to rule out easy to change items.
I believe that the can bus gets EMI interference with worn plugs or bad packs

 

I doubt that - it uses differential signals so such noise will not be seen (which is why it uses that kind of signals).

 

Yes, I understand that it uses differential signals and that common mode signals should be excluded as a differential connection would typically exclude any interference, as long as all signals did not exceed the CMMR of the design. As I have seen strange transmission issues, and communications issues between ECU/TCM and changing coil packs has resolved the shift issues, clunks, missed shifts, flares, I can only assume there is some interference between coil EM and associated wiring that exceeds the CM window.
True root cause may be something else, or not. I would not trying to re-engineer interfaces.

 

It's some other problem I think you'll find. The same engine+trans is in the S-Type and people often have coil/etc faults yet never the issue you suggest.

 

lots of good info here. just bought a 05 xjr with trans slipping and misfires also a 05 vdp with a hum and surge on flat or slight incline but only when engine warms up --but those are for a later date--what I wanted to coment on is have now changed 3 x350 trans fluids and 1 2010 f-150 zf fluid is honey colored ,while mecon lv is red --do not know color of ford sp but to me I don,t think it would be worth trying even though zf is stupid hi .I know everyone says if you have a Honda use only their fluid or else

 

SP is red.

 

just wanted to thank the people on this thread.gave me the idea that fixed my trans problem --2/3 bad coils -----------well im going to start a new thread to tell what happened .so maybe it will help others