As far as I know (and is called out in the FSM), it's mainly just additional sensors, as the ECU is looking for them. There might be a couple of more switches built in as well, but I never really studied the differences, but rather just made a note of the year break offs, and that the FSM called out additional electronics in the "newer models". The only real reason for looking, was that I was trying to learn a little bit about them, and why it seemed they had a higher rate of failure (my wife's Accord is a 4 cylinder AT car), versus the 97 and earlier models (they were very good AT transmissions). I had also spent a lot of time going thru other Honda Accord sites (very few and far in between) trying to get an idea IF there was a specific rough number of mileage at when they fail. While the 4 cylinder version seemed almost bullet proof (if the fluid was changed regularly) that they would go 400K+ miles. But the V6 transmissions were plagued with reliability, from anytime after 50K miles, with a handful dieing before that mileage. Seemed odd, as the 97 and earlier cars with the V6 didn't really have an issue, but the 98 models got more electronics, and started to suffer from problems. In fact it was enough of an issue that on several Honda sites, the big talk was more about going to a 6 speed manual trans in place of the AT (for the V6 cars), once the AT died. There were even a few how to's and where to get conversion harnesses. But most of that info was 10 to 15 years old, and a lot of those places had closed up shop.
I hope this helps, and sorry for the short history lesson.

 

No problem, always willing to learn, otherwise I wouldn't be here, thanks for the class ;-)
From what you say, it sounds like I might be better off with less electronics... I should get the car these next days or next week and will check all this.

 

I don't know if there's anything really different from the 97 cars from the 98 on, versus the ECU setup (for the transmissions anyway). The 97 and earlier cars used a separate transmission ECU unit, versus a combined unit (98-on). That's really the main difference.

 

Up through 1997 there was a cable from the throttle body down to a lever on the transmission, so the transmission knows what you're doing with the accelerator pedal. Adjusting that cable was a bit finnicky…

Another big difference is that starting 1998 that function is done electronically.

 

Hi all,
I'm getting the car back next week and will check all those things and get the error codes if any.
Thanks for all the info.

 

Hi Guys,
Finally got the car back this morning.

New info :
Last time I checked, the engine ran fine and no light came on when turning the ignition on.

This morning when I checked again, the engine idle was ranging from 900-1000 to 1200 rpm going up, down, up,... Moreover, the D4 light stayed on (even though I was on Park) for a couple of seconds and then went off.
The car would jump with every shifter lever gear change.

What do you think? Do you have enough info or do you need me to run a procedure. If so, could you direct me to the best doc (I have the Service Manual and the V6 Supplement if need be).

Any advice welcome, thank you for your time and help.

 

Little up for this thread...
Found out that my IAC valve might be the issue for bad idling (have to check the cooling system and for vacuum leaks too).
But still waiting for your help regarding my tranny problem. Do you have enough info? Should I get an OBDII unit to try to get more codes?
Thanks for your time and help.

 

The D4 light staying on means a code is stored for the transmission. You can get an inexpensive obd2 code reader that should give you a code and at least a place to start testing. Poor/harsh shifting doesn't really help us pinpoint a place to start a diagnosis.

 

Thanks for your help, PAhonda. I'll do that and report back.

 

Hey guys,
Finally found some time to check with a friend... Couldn't find the OBD2 plug in the car!! It's supposed to be on the driver's side above left rest pedal, right? (98 Accord Coupe V6).

Is it possible that it's elsewhere?

Think I'm going to try to clean my IAC valve to fix idle but I heard that you usually end up buying a new one... Any experience with this and if so, any brand you would recommend? I saw prices ranging from 20 to 700 USD...
Thanks for your help.