New symptom Tranny issue 16V 4 door sidekick auto overdrive

[cowtipper]

Still the bucking when I plane out but now the transmission is shifting through the gears very early hold it to the floor and I'm in overdrive by the time I hit 40. Keep holding it there and it will buck and jerk in and out. Shifts firm and tranny feels good as I'm going through the gears. If you pull it down and try to manually shift it through the gears forcing it to produce more rpms before shifting it will buck hard also. Any thoughts?

[Wuppy]

I had similar issues with a nissan pickup. I pulled the pan off the transmission and discovered the filter had worked its way loose, leaking fluid back into the pan around where the filter fit in. I corrected this with a new filter and ensured it was tight, replaced the pan and it was fine after that. May be something to check out.

[jtgh]

3speed or 4 speed, diff . animals, for sure.

bad modulator valve? best guess.
look for oil dripping out vacuum nipple. bad news

tell all that it does right and wrong.

if 4sp there is a specail test mode.
pull TCM and drive it manually (no TCM to messup)
if it drives perfect , then the TCM is bad.
The TCM and ECU both get values from the TPS.
if TPS is bad , both engine and TCM will mess up.
if 4 speed there are codes to read out , is OD lamp flashing.?

(does tranny slip)
does tranny shift early or late
does tranny shift to all gears up and down.
does reverse work perfect. ( and neutral)

The 4sp is complicated. but smarter.
3sp is a brick. ( used in Chevettes,long ago)

[cowtipper]

yes the od light is flashing is that a clue to something? Does not slip at all. When cold shifts pretty normal and will still kick down after a few minutes the transmission will shift to soon and when you floor it it wont kick down sometimes it will try and buck real bad. Reverse and everything works great. If you try and shift manually it will still buck trying to kick out of that gear into another it acts to me like if you try and shift manually it will make the engine even miss a little.

[jtgh]

frist , can you tell us what tranny you have.?
3 speed auto or 4 speed, two completely different animals, they are.
Im not an Auto expert, had the training but dont do them, I do electrics, best.
however most modern Auto use TCm's so that is in my ball park.

OD flashing? I think, this means you have a 4 speed tranny.
if you dont know, then I think ,it is coded in your VIN number , so google "VIN decode" and punch in the number and get the facts on your car.


the OD lamp is connected to the TCM , Transmission control module ( tranny Puter)

when it flashes , this means, the TCM is very unhappy.
it is saying " please do vulcan mind meld and ask me what is wrong"

once you affirm 4sp , you can place a diagnostic jumper on the TCM port and the OD lamp will blink out why it is unhappy.

I can tell you , it will say , it cant shift your tranny correctly...
or something even MORE definative. like bad xxxx solenoid or bad TCC relay ...

possible:
Your Vacuum modulator valve on the side of the tranny sets shift points.
connects to throttle body. this is called the kickdown cable. (is it connected and smooth)
but it works both ways,
prevents , gross hard shifts when accel or decell.

could be bad, but ,id pull the codes
always pull codes from any Puter in any car no matter what it is or what it does.
why operate blind?

some cars have 12 puters. gawd help us........

[cowtipper]

Yes it is a 4 speed tranny. What pins the jumper on the TCM port to get the od lamp to flash codes?

[jtgh]

ahhh, ok, give me moment, will pm docs.

[cowtipper]

We jumped it over and the OD light blinked out code 33. Throttle control sensor is bad. I used the info you provided I owe you a huge thank you it saved me alot of time and money. Jumping it over like that was the only way I was going to get the codes because every mechanics computer scanner in town wouldnt read a Suzuki and I owe you a big THANK YOU.

[cowtipper]

By the way whats the difference between open circuit and short circuit. Either way the throttle postion sensor needs replaced right?

[jtgh]

great job , you nailed it. ( got the code)
the TCM is saying in english.
ECU can not see the TPS vary , because TPS is broken or the wire to TPS is broken or shorted to the body or each other circuit. illegally.

open , means a cut open wire.
short means the wire is connected to something wrong.
a short can be between two wires or to the car metal body.
the cars metal body is ground or the minus side of the battery.
when wires are shorted to the body , we call this grounding Out.
a very bad state to be....

This automatic ( i think) has 2 TPS , one for tranny and one for engine. ( dont have prints on desk now,top of head)

GEE, forgot to say!!! SORRY !
this 4 speed has a test , mentioned in docs ,i sent.
you can disconnect the TCM plugs and tranny becomes a manual transmission and you can drive another 100k miles and no one but you will ever know.

keep that in mind, ( while waiting for spares TCM , TPS , or what ever)

that is the one cool thing about this 4sp . very cool.

It is listed as a test, casually at the end.

The TCM sees the voltage vary from the tranny TPS and is directly proportional to the throttle angle. ( weight of right foot)

The TCM uses this to make nice shift points.
Keep in mind the Tranny does not shift , the TCM calls the shots.
It is the brains. ( in theory ).
This is an early design of electronic transmission controls, how smart it really is , is any ones wonder.


ok ,lets fix this puppy and not go broke doing it or destroying a visa card.

fyi
poster star2525 is driving in manual with a 4sp auto , now.
see posts.