j894

2000 Accord EX.... 2.3l, automatic

Correct me if Im wrong but does the PCM/ECM control the shifting of the transmission with a 2000 accord? or is there a separate computer that dedicated to just the trans shifting?

I had my trans rebuilt over the summer and 2nd gear sometimes shifts slow, the trans shop I had it rebuilt at said the ECM was giving a weird code at the time and should be replaced to make sure it isnt causing the slow shifting condition.

So back to my original question, does the ECM/PCM control the trans shifting or is there another small computer that does it.

HondaPartsHero

http://techauto.awardspace.com/transmission.html

j894

Correct me if Im wrong but it says that applies to 90-93 accords on the website?

From what I understand the newer generation that I have is a different animal

My ECU/PCM is under the center console & radio area.... I dont see another box next to it anywhere, so is everything control just off of this unit?

Targa250R

Yes. '98-02 Accords use a single PCM unit to control both the automatic transmission and engine. The PCM also houses the immobilizer unit, so you must have a matching ignition key when swapping PCMs.

I can tell you right now that your problem likely has nothing to do with the PCM. It's much, much more likely to be an internal transmission problem - doesn't matter if it's been "rebuilt" or not. In most cases, unless it was rebuilt at Honda's own remanufacturing facility, it wasn't done right. I have yet to see an automatic trans rebuild done right by anyone other than Honda.

What code was stored in the computer at the time? If they didn't record it for you on the paperwork anywhere, then they probably have no clue what they're talking about.

j894

Yep that's what I was reading about the immobilizer.

Sometimes it will shift quickly like you would expect an automatic, and sometimes it takes 1 second to shift between 1st and 2nd. Other times while slowing down and getting back on the gas it seems like it hesitates in-between shift from 1st to 2nd. The same when going up a hill at a low speed, while your in the upper RPMs in 1st and it goes to shift to 2nd the rpms shoot up slightly higher than they were in 1st, before it actually shifts to second gear... this is a fraction of second but I notice it.

Im no automatic transmission expert but I have good understanding of electro-pnuematics which work in ways very similar to hydraulics....and it almost like the solenoid dwell time is too long or the solenoid itself is bad, hanging up and not shifting fast enough.

Im almost certain the problem isnt the ECU like you mentioned, but they shop was blaming it on that and I pretty much have to swap out the ECU from them to do anything about it.

I actually have a spare ECU to replace the one I have but before I pay $100 to have the keys programmed to this ECU I wanted to make sure there isnt another unit controlling the trans shifting.