Hello i have a 2003 neon... i was getting the problem ive read alot about with the transmission going into limp mode and throwing p0700 and p0731... i changed out the solinoid unit per what ive read dozens of times, then cleared the codes. Then i test drove it around the block... worked fine at first then went back into limp mode...

So i pulled it back into the garage and gave it the evil eye for a while and i noticed the upper engine mount is trashed... im thinking 2 possibilities, the mount was broken by the engine riverdancing due to the transmission being in limp mode, or the transmission is in limp mode BECAUSE the mount is broke...

Any thoughts? Thank you in advance :-)

 

Ffr...

Got it. I think the engine jumping caused the bad mount... other mounts were fine... waited a little longer and it started throwing p0720 ( output shaft speed sensor malfunction) took that out it was all busted up, replaced it, cleared the codes and drove about 20 miles with no more issues. Before the fix the trans would lock itself in 1st and throw codes within a mile. Im pretty confident it was the problem.