4th gear lock-up issue...

Covers all sn94/95 mustang v8 ecu's.
MyShrink66
Posts: 23
Joined: 2021 Feb 26, 08:54
Location: Montrose, Colorado
Vehicle Information: 1966 Mustang HT, 5.0/4R70W, CBAZA

4th gear lock-up issue...

Unread post by MyShrink66 »

Lock-up was working fine in 3rd gear and would trigger in 4th but then drop out after about five seconds. Data log indicated that the drop out was happening just as TV pressure dropped to 30 psi. Third gear lock-up will hold well below 30 psi. I'm running the trans in Dynamic Pressure mode so I decided to bring FN1615A up a bit. Next road test it refused to go into lock-up in 3rd or 4th. No indication that it's even trying. BCSDC just stays at zero. So...went back to the original FN1615A numbers but still no joy.
So...two questions. What will make 4th LU drop out and did I possibly do something goofy by adjusting FN1615A by 15%. Other than a coincidental electrical issue...which I'll be checking tomorrow...I can't see anything out of whack in the calibration.
decipha
Posts: 4956
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: 4th gear lock-up issue...

Unread post by decipha »

tv pres is irrelevant to commanded lock up

its either calculating excessive slip and forcing an unlock or the srlk max slip ratio to lock function is set too high
MyShrink66
Posts: 23
Joined: 2021 Feb 26, 08:54
Location: Montrose, Colorado
Vehicle Information: 1966 Mustang HT, 5.0/4R70W, CBAZA

Re: 4th gear lock-up issue...

Unread post by MyShrink66 »

I did get an excessive slip code (628) early on but I discovered the OSS connector had come loose (aftermarket connector did not latch), fixed that. No codes now. When it does lockup BCSDC marches from .XXX right up to 1.0000 and Slip ratio goes to .001 +-. So I don't think there is slip when it lock. Would slip ratio to lock function cause it to work fine in 3 rd but not 4th?
decipha
Posts: 4956
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: 4th gear lock-up issue...

Unread post by decipha »

it can


otherwise make sure you dont have some scrambled code in the background
MyShrink66
Posts: 23
Joined: 2021 Feb 26, 08:54
Location: Montrose, Colorado
Vehicle Information: 1966 Mustang HT, 5.0/4R70W, CBAZA

Re: 4th gear lock-up issue...

Unread post by MyShrink66 »

LOL...I ain't smart enough to even know how to scramble code in the background. Only thing I can hope to achieve is following your written instructions. I never touch anything but what you have suggested...and thank goodness you do. Otherwise I'd have to be happy with stamp collecting. Maybe I should be anyway. I have compared and verified anything questionable that I can think of against the original download.

I can't thank you enough for what you do,
MyShrink66
Posts: 23
Joined: 2021 Feb 26, 08:54
Location: Montrose, Colorado
Vehicle Information: 1966 Mustang HT, 5.0/4R70W, CBAZA

Re: 4th gear lock-up issue...

Unread post by MyShrink66 »

Rung out all the electrical connections and found nothing wrong to cause no TC lockup. Finally removed Moates and cleaned the J3 connector. Re-installed Moates and now it works as before...good lockup in 3rd, lockup followed by drop out after about five seconds.
Per Decipha recommendation I lowered FN_SRKLK from .930 as it was in the download to .742 (20%) and it still behaves the same way.
In lockup BSCDC goes to 1.0000, SPD_RATIO SLP % is .001 - 0 in 3rd and .026 - .030 in 4th. I'm sure I don't fully understand what these values mean but it appears to me that my actual slip percentages are well below the original .930 in SRKLK which should be 7% in my mind.
Also...what exactly is BSCDC telling me. Decipha recommendation is to set at 64 which I have done.
Will it hurt anything to drive long distance with no 4th gear lockup. I wouldn't think so...other than MPG...but I gotta ask. This car IS making a long trip in May and I WILL reinstall the AOD if necessary.

Thanks again for any advice or ideas.
decipha
Posts: 4956
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: 4th gear lock-up issue...

Unread post by decipha »

post your tune file
MyShrink66
Posts: 23
Joined: 2021 Feb 26, 08:54
Location: Montrose, Colorado
Vehicle Information: 1966 Mustang HT, 5.0/4R70W, CBAZA

Re: 4th gear lock-up issue...

Unread post by MyShrink66 »

Bin file attached, thank you Michael.

Did I do this right?
Attachments
U4P2_200705_Evans_210225.bin
(56 KiB) Downloaded 216 times
MyShrink66
Posts: 23
Joined: 2021 Feb 26, 08:54
Location: Montrose, Colorado
Vehicle Information: 1966 Mustang HT, 5.0/4R70W, CBAZA

Re: 4th gear lock-up issue...

Unread post by MyShrink66 »

Bin attached.
decipha
Posts: 4956
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: 4th gear lock-up issue...

Unread post by decipha »

maybe 7daa to 7de3 was corrupted

give this a go and LMK
Attachments
Evans_210225b.bin
(56 KiB) Downloaded 233 times
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