I did the JMOD shift kit in my 1998 mustang GT and after I did it the OD light was flashing and car would not go into gear. I ended up replacing the valve body and wiring harness and car doesn't want to shift. Will somewhat shift on low acceleration but not the best. Transmission fluid dipstick says it's full and MLPS is aligned so I am so lost at this point and have zero clue what to do.
Transmission issues
- Thread starter Sparty443
- Start date
We have a fantastic transmission guy that hangs around here, but as of recent he has been super busy keeping him away from the forums. Perhaps the powers on high around here can summons him.
07GtS197
Well-Known Member
Is it throwing any codes? If it is shifting then the electrical side is working. Just spitballing but if it’s not a mechanical problem it could be low line pressure.
Man really could use him
Here’s the codes it was giving me. It was shifting fine before I messed with the valve body so not sure it would be the line pressure unless filling new fluid could mess with that?
Attachments
07GtS197
Well-Known Member
The first two codes have to do with the epc solenoid that regulates line pressure, which indicate low or erratic line pressure. You’re going to have to drop the valve body again and check the epc solenoid. It either isn’t plugged in or failed.
The new valve body came with new solenoids so I’m not sure if it would be that?
Could low or erratic line pressure cause this? At one point it was low on fluid so could have gotten air in there?
07GtS197
Well-Known Member
Yes it can cause that and just because something is new doesn’t mean it’s good. Could be bad out of the box.
Wmac
Active Member
The info I have indicates that the first and second codes are for manual trans, so should they not be ignored?
P1783 indicates transmission over-temp condition, often triggering a flashing o/d light, reduced engine power, or limp mode.
Did the new valve body include the separator plate?
P1783 indicates transmission over-temp condition, often triggering a flashing o/d light, reduced engine power, or limp mode.
Did the new valve body include the separator plate?
Wmac
Active Member
Hmmm, disregard what I said above about the first 2 codes, goggle search does indeed refer to the epc solenoid.
