240sx auto transmission

[2the40]

Car: 91 240sx w/ 135k I hope you guys might have some opinions on this. My auto transmission has been having two kinds of problems. First, it won't shift into 2nd when put in drive, it just revs. It has been doing this since 120k. Second, it has recently been getting stuck in other gears like 2nd or 3rd. I have changed the fluid and filter twice with the correct stuff, but it continues to do it. I also used Seafoam to clean it some time ago. It shifted great for about 5 minutes but went back to getting stuck. It happens about half the time I try and drive it. I hope someone might have an idea what is wrong with it. Is it something I might be able to fix? Or should a dealer look at it?

Thanks

[s13sr20chris]

no second? and getting stuck in gear? that really sounds like a mechanical failure to me.

[2the40]

That's what I'm afraid of. I think the previous onwner put the wrong type of fluid in some time ago. All I know is that to get to 40 mph I have to be at around 5500rpm. When it does shift it slams into gear.

Could it be a random sensor, or the throttle position sensor? I have heard that this might be a cause, but I don't know how to check it or where to find it.

[180fan]

you said you used seafoam. Not in the transmission right?

[2the40]

Yup, I used the Trans Tune stuff. I had read some posts on here about that working. I put that in around 3k ago and it didn't change it. This problem with it getting stuck in 2nd or 3rd has only been happening for 2 or 3 weeks.

[2the40]

I'm taking the car to the dealer this afternoon to be looked at. Is there anything I should ask them to look at? Something specific?

BTW: what is cheaper a replacement auto, or a 5spd. swap?

[vacnsewmedic]

Not trying to cut in on your thread.........but Whats up .....

Yo...Im having a similar prob.....except my Overdrive light stays on and my gears all switch fine except for getting into 4th gear.....im riding 55 mph at 3500rpms......but will not switch to 4th should i mash the pedal down and see what happens......

some ppl say ......Speed sensor, ( I think it maybe a Temp Sensor not kicking my transmission into 4th as I heard this is suppose to happen?? I hear when the engine warms up it allows the transmission to kick to 4th by a Temperture sensor,,,,is this true?

[2the40]

No problem...

I took my car to the dealer and they said it needs to stay there till Monday so they can finish looking at all the sensors. They mentioned both the temp, and speed sensor. I'll post back when they come up with an answer.

It is funny you mention the overdrive light, because when I take mine out of overdrive, the car won't shift out of first at all! Taking it out of overdrive really screws my car up.

BTW, when I mash on the gas it just redlines, I don't recommend that.

[vacnsewmedic]

thanks man,

ill wait to hear from you and go from there, but hopes the best

since my overdrive light doesnt blink.....it just stays on when i cut the car on, im assuming its a temp sensor.....or something.......

lemme know 2the40

[2the40]

Well I got it back today, and the dealer said they couldn't pin point any one problem. The said they checked all the sensors and none were bad. My ECU wasn't throwing codes and they can only guess what the problem is.

To make a long story short... they didn't replace anything and the only suggestion was that my transmission mount needs replacing. Their thoughts were that if the trans was leaning to one side, it could deprive certain parts of the trans of fluid. They said my current mount looks decent, but that is the only thing they can think of, besides a worn-out transmission.

Sorry I couldn't help you man, I will probably take it to some other shops when I get a chance. I'm kinda dissapointed.

O well.

[vacnsewmedic]

damn, i thought when u took it to a nissan dealership you would expect a determination,,,but damn,,,,I just cant think its the transmission....because if its shifting through the first, second and third.....i would think its electrical not transmitting it to switch to fourth.....

Well, imma try a couple of things myself,,,,,If i find something out tonight ill holla back.....im pulling out all my related sensors and testing them to see if one might be blown.......

adios.....

[2the40]

Tell me about it, I think they were just honest and didn't want to sell me something I might not need. So I guess they were good to me.

It sound electrical to me to, so I'm not going to give up...

Good luck w/ yours.

[vacnsewmedic]

hey 2the40

chris one of the nissan online mechanics, mentioned checking the tcm pin 19 for power or ground...

imma check mines out in the morn.....

adios dude, ill let ya know

[CDE]

hey 2the40

chris one of the nissan online mechanics, mentioned checking the tcm pin 19 for power or ground...

imma check mines out in the morn.....

adios dude, ill let ya know

Where is that?I also wanted to check mine, but I think my transmission problem is much different. I have a shimmer when I'm accelerating, and it shifts HARD into 2nd unless I floor it, or accelerate very slow. Other wise its kinda like a jolt when it shifts. Does anyone figure this possibly could be solved if I just get it serviced?

[s13sr20chris]

ah, so you have 2nd but it shifts hard? that could be a line pressure issue. one thing you can do is drop the trans pan and check all the grounds on the valve body. nissan is having an issue with that on the new altimas. when i say check i mean test the voltage drop across the ground.

[2the40]

hey 2the40

chris one of the nissan online mechanics, mentioned checking the tcm pin 19 for power or ground...

imma check mines out in the morn.....

adios dude, ill let ya know

Thanks man I think I will try that. If I have some time this weekend I will tear into the car. The other day my overdrive light started to blink when I turned the car on. This is the first time I have seen it do that.