Hi......what is the "normal healthy" A/T behaviour (O/D is on) when you remove your foot from gas and the A/T is just about to shift to 4th gear ? mine (97 auto) makes RPM quickly dips to around 400-500 then goes to 900-1000 (without pressing the gas pedal) while cruizing each time I quit the gas before the A/T shifts to 4th.....I cleaned TB , MAF ,IACV really well,new spark plugs , air filter , fuel filter ......nothing seemed to work.............

 

when the last time u did tranny flush. It could help. Any shift issues in other gears?

Edit:

Kinda sounds like an electrical issue with the tranny too. Almost like an improper groound for tranny. Try running a ground wire from battery to tranmission housing.

 

wait wait wait. are you saying you could be cruising and you let go of the gas just before it shifts into 4th gear. but all the while that happens it idle's at 900rpms?

 

OP correct me if i am wrong...(and its been awhile since i have driven auto ) But i think he is saying, when driving and jus before the car is about to shift into O/D, he takes the foot off teh gas, which is prolly 40-50mph. Jus before the car shifts up, the RPMs will dip to like 400-500 RPM and then catch itself, switch to 4th, and RPMs will rise to where they shd be at for 4th gear.

Sounds like an electronic issue like a soleniod or A/T switch is sticking. Might jus need to replace or maybe a tranny flush will fix. Dont sound like tranny is broken or really slippin to me.

 

you know i think i made a thread bout something similar. except i said that when in 4th gear around 40-50mph my rpms goes straight down to idle (when i let go of the gas of course). thats the reason i asked.

 

It may be that your ECU/TCU just senses that you let off the gas, and decides against going into 4th gear and/or T/C locked mode.

I know my transmission loves to shift into 4th gear at around 25-30ish mph, and then if I go slightly faster, around 32ish mph, the TCU also decides to lock the T/C.
It's annoying at times, so I adjusted my driving style to try and avoid too much stress on my transmission.
I do know there is a O/D OFF button.. /does not like using it.

 

i didnt read any of these other responses but my auto used to do that. if i took my foot off the gas right b4 it was gonna shift the rpms would dip way down to like 500 rpms and then shift go bak up to 1500 rpms or w/e where it was supposed to be once it shifted... it also did it in 3rd sometimes too.

 

well according to the service manual if it's in "D". it's normal.
i thought something was wrong with mine till i drove my dad's 97 gxe. his did the exact same thing.

oh yea his lock up early too.
Akiyukio your not adding any stress to your trans if you wanna speed up the tcu has enough intelligence to unlock the torque converter and downshift to a previous gear.

 

my 96 maxima does this when someone hits the brakes all of a sudden & it was about to shift into 4th, it drops to 500 RPM then goes back up & drives normal..

has never given me any problems, and it's always done that since i got the car (2 years ago)

I always use OD too.. i wouldn't recommend not using it.

 

lol the problem I have with my tranny is that whenever I let go of the gas and slightly tap the brake and let go all within a second, my RPM's drop to Idle. It doesn't matter how fast I am going. This only happens when I tap the brake pedal quickly.

 

^^^ i think with you your t/c is locked it does'nt release until you go lower than 40mph (well thats what mine does). or if you tap/press the brakes.

on the highway i could be doing 60mph at 2k rpms. let go of the gas still holds. tap the brake, the rpms drop.

 

^^^Yeah exactly. I was thinking it was the torque convertor but wasn't sure. AT FTL lol

 

can the T/c even be replaced? Or does the entire tranny need to come out

 

I think the transmission needs to come out before you can replace the T/C. I could be wrong.

 

If your transmission is warm (not cold) and you drive granny style (very gentle) it will:

- Lock the torque converter clutch (TCC) in THIRD gear around 28mph, still in third.
- Shift to fourth (overdrive) before 40mph, at which point rpm will drop below 1,400rpm

(When the transmission is cold the TCC does not lock up at all.)

Also be aware that:

- This automatic transmission has sprags for all gears except fourth.
- With overdrive OFF, the third gear sprag is disabled by a clutch.
- Put the shifter in 2 and the second gear sprag is disabled too.
- Put the shifter in 1 and the first gear sprag is disabled.

So, what is a sprag? You can look it up yourself, but the effect is that the engine will turn the wheels but the wheels will not turn the engine. So, if you take you foot off the gas pedal with overdrive ON while the transmission is in THIRD the engine will drop to idle because of the sprag. It is possible for the engine computer to not react fast enough so that the engine rpm briefly drops below normal idle then recovers.

Finally, if the TCC is locked in FOURTH gear and you let off the gas pedal it stays locked and the engine rpm doesn't change, but as soon as you hit the brake pedal it UNLOCKS and engine rpm drops.

Pay attention to what your transmission does when you drive so you can learn what is normal for it.

 

Sprag is a locking mechanism

Some transmission use ***** and some use sprags.

 

iduty thanks for clearing that up.
you answered my question.
cuase almost every car i drove the rpms seem to hold when you let go of the gas, but the 4th does'nt...well between 45mph and below.

 

I think it is normal. I have a 97 and a 96 and you can make them both do that if you back off the pedal right at a shift point. Basically you have caught the car in "neutral" and it takes a second for the computer to correct.

 

this help my issue

 

how much will this cost me?

 

stop spamming and posting silly comments...definitly a bad start for you

 

 

3.0 1999 maxima A/T -behavior. I don`t uderstand when car switches on 3`d gear to 4`th gear. Is it normal that on speed 68 mph engine is on 3200 rpm ?

Does anyone know what is top speed on 3´d gear ? I try`d to accelerate little bit to speed 112 mph it was 5500 rpm.
When i am cruising around 65-70 mph and push o/d off/on nothing changes..

 

Now i have done diagnostic as well. But i dint found any error codes, only knock sensor.
Do i need to replace solenoid pack or first just flush tranny ?
Overall gearbox changes gears very smoothly, but no 4th gear.

 

you need to pull the TCM codes specifically. go to a shop.

 

to pull tranny codes you dont need to go to a shop. in the fsm it has step-by-step instructions on how to retrieve the codes...or judgments is what nissan calls it.
then it flashes the OD light.

 

I was trying to get TCM codes, but nothing O/D dont blink. Maybe this is a problem.

Also i checked tranny oil and it was much more over "Full" mark. I belive this could be also problem.

 

i was about to tell you your car is fine. untill i seen YOUR post and not the original poster.
hmm...how about when you first turn your car on.
does the overdrive light come on for about 2 seconds then go out?
did you look in the online fsm? you cant retrieve tranny codes by going to autozone.
you can do it yourself.

i'm going to give you the directions on how to do this without the consult scan tool.

Let the car warm up to operating temperature.
Turn the ignition switch off. wait for 5 seconds.
Turn the ignition switch to "ON" position (engine off).
Move the shifter to "D" position.
Turn ignition switch to "OFF" position.
Set the overdrive switch to "OFF" position.
Turn the ignition switch "ON" again (do not start engine).
Wait for more than 2 seconds after ignition has been switched on.
Move the shifter to "2" position.
Set overdrive to "ON".
Mover shifter into "1" position.
Set overdrive switch to "OFF".
Depress gas pedal full and release it.

and the light flickers.
these are called judgment's.
it flickers but with each judgment the light flicker's the longest.
for example lest say you have a judgement code for throttle sensor circuit.

' represents the quick flicker's while ~ represent the long flicker.

' ' ~ ' ' ' ' '

but do the bulb check first.
hope this helps good luck.

 

Now i have tryied this also. But O/D off light just stays light on after "Depressssing gas pedal full and releasing it - no flickers !!

 

hmmm...the light just stayed on?
(which tells me the od switch is set to off, which light is on) are you sure you tried it right?
if the light stayed off it means tcu no good,selector switch, tps disconnected.

 

Now I visited auto mechanic and he found some problems.

1. alterator was bad ( charging 13,2-13,3 V )
2. TPS is not working ( no signal )

So on next monday these parts will be replaced. I hope this solve my problems. Overall mechanic said to me that tranny isn`t slipping and changes gears very smoothly ( R-1-2-3 ).

vallo

 

but you have no 4th gear?
hopefully this solves your problems.
as i found mine.
i did the test myself. got line pressure solenoid code. and tps code.

 

yes i have no 4th gear. I have already calculated that i have to change solenoids pack as well. I hope that to change solenoids pack i dont have to take tranny out.

 

no. but you have to remove the valve body...or so i read in the how-to, when changing out the solenoids.

maybe someone can provide some info.
when removing the valve body; will the check ***** and springs pop out.
does it have to stay in one position so nothing will fall out?

 

I just replace all the solenoids. It's easy. http://forums.maxima.org/4th-generat...st7426861.html This is what you see when you take the pan off http://forums.maxima.org/album.php?a...ictureid=10114