Automatic Downshifting

acura
integra
transmissions

#1

So i just bought this 97 integra gs with the B18B motor (Non Vtec) It had a bad transmission so i replaced it with a japanese take off that has about 35k on it and it seems to be…off, so here it goes, When accelerating medium to hard it shifts like a dream all the way 1-4, but when driving through town at slower speeds it seems to have a real problem knowing when to shift and randomly downshifting hard(sometimes so hard it clunks) it will even downshift twice sometimes resulting in engine breaking like i was trying to drive it like a manual tranny. it seems to have the most trouble between 2nd and 3rd but it will happen between all gears throughout the day. so my question is should i pull my newish tranny and take it back and gamble that the next one will be better or is this an external problem that i can fix? any help would be greatly appreciated.


#2

well you can take it back or just have it inspected to see whats wrong, maybe a sensor or something cheap. if not have it rebuilt, then you wont have to worry. DONT use aamco or big chain tranny shop. ask around for recomodations, so as to not get ripped off. good luck


#3

Do you have a manual that applies to this engine/tranny configuration? It sounds like the kickdown isn’t working right. I don’t know if there’s a cable on this transmission or a vacuum system or an electronic system or what, but it does definitely sound like an out-of-whack kickdown to me. I’ll bet something isn’t connected, doesn’t go together or is very out of adjustment.


#4

Honda automatic trannys have “grade logic”, which is a control feature that holds a certain gear while climbing a hill. It also can downshift the transmission when descending a hill. You may need to find someone who understands the tranny computer and how it relates to the engine, road speed, vacuum, etc. Maybe a software adjustment, fix, replacement is in order.


#5

Ya this tranny does have a throttle positioning cable that is a little worn so i am replacing it today. i took it to a local tranny shop and he said it was the cable which i believe could be part of it but i don’t think my current cable is malfunctioning THAT much but i will see. I would have to agree there could be something wrong with the pressure getting to the tranny at low rpms or maybe an electronic sensor/control module malfunction? Thanks for the advice and any other suggestions are greatly appreciated. I will keep you posted on what happens.


#6

so i was on my way home from the dealership with the new throttle position cable ready to change it out when i got home and about half way home my speedometer and odometer stopped working and almost insantly my car stopped searching for its gears! It still has a slight clunk when it downshifts to 2nd and kicks like a mule now when going from reverse to drive but otherwise drives alot better. So apparently my speedometer was messing it up some how.? ? ? I am still going to try and fix everything else and see how this tranny does when it is at its best before i return it. although if it still clunks on downshifting isn’t that bad???


#7

Flaky VSS (vehicle speed sensor). It will both screw up shifting and cause the speedometer/odometer to malfunction. Apparently in your car, when the VSS gives up the ghost, the transmission control reverts to a default shift program.