99 Honda Civic coding P0740, what is your advice?

Question

99 Honda Civic DX code: P0740 Shifts hard at higher rpm, advised by trusted mechanic to replace solenoid, this site says no, advised by another trusted mechanic to use Sea Foam Trans tune, what's your advice?

Answer 1

Hi there

There is no reason not to replace the solenoid. Essentially it's best to check the condition of the fluid because its common for solenoid issues to be the result of low or dirty atf.

Here is some info on the code.

P0740 HONDA - Transmission Lock-Up Control System Fault

Read more: https://www.autocodes.com/p0740_honda.html