Weird AT tranny problem fixed

[ICEMAN707]

For the past couple of months I've had problems with the AT tranny slipping on me and not engaging gears at the right RPM's. Last night it dawned on me that I swapped the ECU unit with one I found from the junk yard months ago. I thought to myself, maybe the AT transmission has sensors in it that tell the ECU what the speed is and in turn the ECU tells the tranny to shift at a specific RPM. So if I had the wrong ECU, this would be a problem.

So I thought I might have swapped my ECU with a manual one. So I swapped back my old ECU. (Thank God I still have it) Everything is back to normal. I'm so glad this problem was fixed because it's been irritating me and thought I might have had a shot transmission in my hands. I may have a bad water-soaked ECU or manual ECU from the junkyard. This might be some good info for some people with AT transmissions. :rockon:

[shepherd79]

if you have 89 accord with auto tranny, it has some solenoids on top of the tranny. noone sure what they do, but they do something.
it is never a good idea to swap 5 spees ecu for auto ecu.

[AccordEpicenter]

the ecus are the same for 5sp and auto guys, and has absolutely no control over the tranny in these cars. Our autos are fully controlled by a hydraulic valvebody

[ICEMAN707]

Well, I guess the ECU I got from the yard was just water damaged then if a 5 spd ECU doesn't matter. All I know is, the car runs alot better now.

Weird thing is with that ECU, only the tranny was having problems, nothing else. So it can't be a water damaged ECU. I dunno what it is but I believe it has something to do with the ECU cus swapping them out fixed my problem.

[AccordEpicenter]

somtimes the ecus do rot, especially in the location that they are in, somtimes a puddle of water develops under the seat and they get all kinds of internal corrosion and run very wierd and stop working eventually. Usually when the ecu throws a solid cel then its toast, at least in a honda/acura. Dont know how it coincides with your tranny problems though

[ICEMAN707]

Yeah I never messed with my TV cable. When I changed out my fast idle valve to fix my idle problem, that's when it started. And I just remembered now that I also swapped out ECUs. I looked at both and they both have the same matching #'s and are identical. I don't remember what type of 3gee I got it from, whether carbed, EFi, 5spd, auto, OR 86-87 or 88-89. I'm gonna check the auto tranny today and see if there are any wires coming out of it that might have something to do with ECU control. Like shepherd said, there are some solenoids there.

[john]

ya I always hear all this talk about the computer controling the trans or the ecu. Problem is there are no wires going to a 3g auto trans If you have senor's you better th etrans #'s is not a 3rd gen trans you have

[smufguy]

i have never come across a solonoid on a auto tranny. anyways, the best thing to do is put the car in neutral and see how the engine sounds without load, then put the car in drive, pull the ebrake and hit the gas slowly (without dragging your rear tires) and see hwo the engine sounds under load. most of the time, its probably the motor thats being weird. i mean, we dont even have an electronic overdrive do we?



the ecus are the same for 5sp and auto guys, and has absolutely no control over the tranny in these cars. Our autos are fully controlled by a hydraulic valvebody

thanks for reinstating that. I dont know how many times we have talked about it.

[POS carb]

i want pics of these solenoids. As far as I know they are 100% hydraulic with NO electrical connections, only a cable that is comparable to a kick-down cable on old domestics. (and I've rebuilt one but it was an '87 model, the only difference in the 88-89 models should be a beefier 2nd/4th gear clutch housing)

[toolnon]

i want pics of these solenoids. As far as I know they are 100% hydraulic with NO electrical connections, only a cable that is comparable to a kick-down cable on old domestics. (and I've rebuilt one but it was an '87 model, the only difference in the 88-89 models should be a beefier 2nd/4th gear clutch housing)
I have a tranny with these solenoids on it. See my question posted under (LXI with solenoids on transmission 8/19/05)