I had some shifting problem a few months back and a flush at the dealers cured it.

Recently though, I am facing another problem. It appears that as the ambient temperature drops to around 45-50 deg F, the transmission does not shift into the 4th (electronic overdrive ?) gear. Even if I drive 80-90 miles and the temperature gauge shows normal operating temp (center) the transmission does not shift. On a warm day like 65 deg F or higher, everything seems to work alright.

Any ideas?

Thanks!

 

i believe that the atf fluid is cooled by the radiator. Maybe somehting wrong in that connection. I guess the ecu reckons that its too cold, and is holding it in third (for ever) until the car supposedly warms up.

 

thermostat? ,maybe

 

vishnus diagnosis sounds right to me.

 

Its all dependent on what the ECU THINKS is going on, so if a sensor is bad, it'll be receiving bad information and therefore not upshifting like it should.

 

thanks for the posts. Ken, which sensor(s) are you referring to? Is that something I can check myself or will I have to take it to a shop?

 

My 2.5 does the same thing but its not 4th gear we are talking about... its the torque converter lock up....

 

torque converter lock up? what is the remedy for this problem?

 

Well I've been having the same problem. I had my acura mechanic change the thermostat and it turns out that the fluid is bad. I was told it was changed out like 1.5 yrs ago and someone checked it out a month ago when the starter was changed out. Turns out they must have never touched and the fluid is bad. the tranny is going and needs to be changed out. I'm stuck with either selling off or 1K for the change out. i hope yours isnt going too!

 

Isn't the torque converter supposed to lock up at a certain point? I'm pretty sure it is...

 

Yes the torque converter does lock up... its supposed to. Mine doesnt lock up when cold...

 

so when it locks up, if feels like a pseudo gear change right - revs drop about 100-200 rpms? I feel the change in my TL, but not so in my accord. Is it always apparent when the torque converter locks up? Anyway, to find out for sure?

 

I am thinking of locating the solenoid for the TC valve and attaching some LED or something so I can get a visual indication of when the TC receives its signal. Either the solenoid coil is bad and does not actuate when cold or the ECU is not sending signal at appropriate time.

Would anyone happen to know where is the solenoid located? Does OBDII connector provide any information on drive train issues?