Hi! Really appreciate any insight here. Have a 2003 Honda Accord. The majority of times, it shifts just fine, but on occasion it will refuse to go into Overdrive, and you have to shut the car down and let it rest for it to change its mind, if it is going to change. I brought it to the local mechanic who can't find the problem (or replicate it, of course :-)). It isn't throwing any codes. Random side notes in case helpful (may or may not be related): 1. at the same time, the cruise control stopped working altogether, 2. when tried to unlock the car at one point once this started, it cracked all the windows, - it has never done that before, 3. the O2 sensor has been bad and not replaced for years. Typical manifestation - getting on freeway, shifts smoothly to 3rd and stubbornly stays there for the duration no matter what I do (going to D3 and back again, foot off accelerator, etc.). Problem started a couple of weeks ago.

 

Is the D4 light flashing? I'm guessing the check engine light is on all of the time due to the O2 sensor?

The mechanic may have done this, but I'd scan for codes. If you don't have a scanner, you can stop by your local parts store and they will scan for codes as a free service. Post the actual codes on here.

 

Thanks for responding! The local mechanic is still stumped. The D4 light isn't flashing, and they checked for codes, but didn't find it throwing any.

 

A few more questions. Was any work done on the car before you had the shifting problems?

Is the cruise control not working all of the time or only when you have this shifting issue?

When did you last change your transmission fluid?

 

No work was done on the car, say, for 6-10 months before the problem started. The cruise control doesn't work at all since the problem started, not just when having overdrive issues. Don't remember when the last change of trans fluid was. The shop checked that and felt the fluid looked pretty good and levels were good - but probably been a while.

 

I'd probably treat the cruise control and the shfiting issue as separate unrelated problems for diagnosing purposes. Maybe troubleshooting the CC will lead to a common isssue like the PCM that could cause both problems, but you don't want to assuem the PCM is flaky in this circumstance without troubleshooting.

My TSX is similar to the 03 accord and the windows will roll down if you press the unlock button on the remote twice and don't release the unlock button on the second push. You may want to look at your owner's manual to see if your 03 has this feature.

You mentioned you've had an O2 sensor issue for a while. Is the CEL on all the time? Did the mechanic read any codes for the O2 sensor?

I would change the transmission fluid if this was my car to get fresh fluid in there. The transmission holds about 7-8 quarts of fluid, but only 3 quarts drain from the pan. The best way to exchange the old fluid with new is to drain the 3 quarts, top off with 3 quarts, drive for a bit to mix the fluid. Then repeat this two more times (3 drain/refills, so 9 quarts of fluid needed). I'd drive for a day or two if I was doing myselft, but it sounds like you are having a shop do the work. The shop may have their own method.