what makes an auto tranny shift?

[evil88accordLX]

here lately if i dont give the car enough time to warm up in the morning, she doesnt like to shift. the tranny fluid is good, the car runs like a top. id like to know what makes the car shift (she is carb'd), and if possibly there is some kind of controller that needs replacing or cleaning or something. auto trannys are like greek to me, so any info would be much appreciated.

[BITESIZE]

Try adjusting your tranny, I just did this and learned how from the how too...

http://www.3geez.com/forum/showthread.php?t=40885

[Hauntd ca3]

autos rely on hydraulic pressure from a govenor on the output shaft to send a pressure signal to the appropriate shift valve when its time to shift.
if the govener ir shift valves have some shit in them, they wont move until its warm and things have expanded enuf to allow things to move.
running a trans flush through it and changing the fluid mite help but this sounds just like what happened to my trans before it decided to stop shifting all together
unfortunately honda trannies dont have an external filter or one that you can change unless you pull the trans to bits.
i'd do a 5spd swap or if you want to stay auto, put in a recon one and stick a filter in the cooler line

[Dr_Snooz]

The mechanism that actually shifts is the valve body. It's full of aluminum plungers that score and wear and hang up. Autos are pretty complicated really, but your options for fixing them are fairly limited. Start with a flush. If that helps, do another. If it doesn't, rebuild it. If it slips, there's nothing to be done but to rebuild it.

You might start with a better description of what "doesn't like to shift" actually means. Does the car wind real high before shifting? Does it jerk and bang? What? Depending on what's actually happening, it might not be the tranny at all.

[88Accord-DX]

The mechanism that actually shifts is the valve body.
You hit the nail on the head. With todays cars, the TCM or PCM controls that function.

[2oodoor]

on these accords the throttle valve in the tranny controls the shift before the internal governer, that is why it is important to keep it adjusted properly. The TV, throttle valve is part of the valve body function, and is physically controlled by the movement of the throttle via cable, lever.
Newer cars this is accomplished by the ECM thru readings of the Throttle Position Sensor, Speed Sensor , and electronic solenoid valves at the transmission.

[Hauntd ca3]

the throttle valve controls where and how it shifts to an extent.
the throttle valve has a spring on one side and is feed gov pressure from the other side.
a shift wont occur until gov pressure over comes the throttle and throttle spring pressure and then gov pressure gets directed to the appropriate shift valve and the next gear is selected.
the harder and faster you push the throttle the higher in the revs it will shift since throttle press is higher and the gov pressure has to be higher to overcome it.
the throttle valve controls kick down as well.
the most critical part of honda trannies working properly is just making sure they are serviced
when they are meant to be.
for best results and long life use a place that can back flush the trans to push all the shit out of the valves and servos

[evil88accordLX]

You might start with a better description of what "doesn't like to shift" actually means. Does the car wind real high before shifting? Does it jerk and bang? What? Depending on what's actually happening, it might not be the tranny at all.

okay, "doesnt like to shift" means that for about the first mile or two, if i dont let the car warm up, it just winds really high before shifting. there is no banging, clunking, slipping, or anything that would lead me to believe it anything more than something getting stuck due to the age of the car and not being warm. and it only happens in the morning if its cold. leads me to believe that something is just sticking. i am a crackhead about doing routine maintenance to the car, so i dont think its going out.

[Blkblurr]

Don't forget about the hydraulic pump that produces the power needed to move the shift pistons that actually do the gear shift. If the pump is worn and not producing enough pressure you will get the type of problems described here.

[GraniteLXI]

okay, "doesnt like to shift" means that for about the first mile or two, if i dont let the car warm up, it just winds really high before shifting.

Oddly my 3gee did the same thing one morning, it shifted later then usual but everything still worked fine. But, as I said it only happened one morning and has never happened since, even when driving it and not letting it warm up. I would flush your fluids as everyone said and see what happens from there.

[nfs480]

Mine has done this for as long as I can remember when cold. Maybe its nothing to worry about?

[evil88accordLX]

Don't forget about the hydraulic pump that produces the power needed to move the shift pistons that actually do the gear shift. If the pump is worn and not producing enough pressure you will get the type of problems described here.

where is this pump you speak of? is it external or actually inside the tranny casing?

[Dr_Snooz]

My miserable German car does this every morning and the shop tells me it's designed to do that. Whatever.

Flush your trans and replace the fluid more often. Use good fluid and it should clean up over time.

[Hauntd ca3]

okay, "doesnt like to shift" means that for about the first mile or two, if i dont let the car warm up, it just winds really high before shifting. there is no banging, clunking, slipping, or anything that would lead me to believe it anything more than something getting stuck due to the age of the car and not being warm. and it only happens in the morning if its cold. leads me to believe that something is just sticking. i am a crackhead about doing routine maintenance to the car, so i dont think its going out.

that sounds like shit in the shift valves to me.
there is no really easy way to fix that bar getting the trans back flushed with the proper machine or rebuilding the tranny

[2oodoor]

Mine has done this for as long as I can remember when cold. Maybe its nothing to worry about?

If it is a carbed car, the thottle control and fast idle controler holds the throttle open further than when it is warmed up, this will affect the TV cable home position and operation. It probablly is good indication the TV cable needs a slight adjustment if the gears are holding on too long that it shows as an annoyance.
But on the other hand you should not be having to hold the throttle open any more with your foot to achieve motion, which would make the TV in the same position as the thottle is opened. It could be more sensative on some carbs as to how much thottle opening is needed, depending the conditoin of the carb I suppose.

That said, I have corrected shift issues by cleaning the throttle body in FI cars of other makes.

[Blkblurr]

where is this pump you speak of? is it external or actually inside the tranny casing?

the pump is inside the tranny and is driven by the input shaft from the engine. Some trannys have more than one pump but I'm not sure about the 3geez.