Need some help. My daughters 03 Civic, automatic, with about 230000 K on it has started doing a strange thing. When driving the automatic transmission seems to shifts fine from 1st to 2nd and into 3rd usually but at higher speeds the transmission seems to get stuck and wont shift under acceleration. If you drive the car and back off the accelerator just for a second when the rpm hits around 4G the car shifts fine. Down shifting seems fine and no funny sounds when shafting. I checked ATF levels and was a bit low but nothing crazy. Drained the old ATF fluid and put fresh oil in and its still doing the same thing. Any ideas on how to diagnose the issue. Could it be a vacuum leak? Im just a back yard wrencher so any help or direction would be great.

Thanks

 

The simplest explanation might be that you're not using genuine Honda transmission fluid; that could certainly cause delayed engagement of the gears.

 

There are like 4 or 5 solenoids that have to do with the transmission shifting, you might want to take them out and check to see if the screen mesh is clogged. Another thing that might help is to bench test the solenoids to see if they’re engaging when voltage is applied.

 

Thanks for the replies, definitely not the trans fluid as the car has been shifting fine and recently just started acting up. I double checked to make sure it was the correct fluid type. As for the 4 or 5 solenoids that have to do with the transmission shifting any direction on where one should start checking? will try and get to this on the weekend and will report back.

Thanks

 

I’ll get you all the info at my earliest convenience.

 

Hi Guys so hooked up scanner and am not getting any trans codes. The only code is the po420 catalyst syst efficiency below threshold bank 1. is there anyway that can be effecting the shifting? The car does seem to be down on power a bit also.

 

Both of the cars I’ve owned have had similar problems. The first one I ruled out to be a failed transmission and I sold the car. Secondly I found that the O2 sensor gave me the same problem weird shifting and loss of power. But more recently I had my Cam position sensor go and it was doing the same thing. Idk if this is relevant but I hope it helps

 

Hi j-charb, did your car give you any code errors when this happened? I have tried a new duel linear solenoid and just now the transmission shift control solenoid with no change in how the car is running. Power is down, car only up shifts when you back off the accelerator and struggles to get up to hwy speed. I'm scratching my head on what to try next?