I have a 2001 Nissan Maxima 20th anniversary edition with the 3.0 engine.

I have a problem with the transmission after driving the car for 30+ Minutes in 65+ degree weather, The transmission locks up and the car wont go pas 20mph!

it only happens when is kinda warm out side and, In stop and go traffic.

I have been to transmission shops and they cant find the problem :/ They say the car is fine.

BUTTTTT!! before all of that started One day the catalytic converter cover or heat shield fell of!

Could the catalytic converter be heating up the transmission in witch heat makes metal expand causing the transmission not to go into 2 second gear? :O

Any help? What do you guys think?

 

Sounds more like plugged cats then it does a transmission issue

 

Have a look in the FSM for some troubleshooting steps.

 

went to a muffler shop or w.e, They checked the cats and said they were fine. :/