94 240 conv with AT shift problems

[deblouthomas]

I had a black 93 that did that exact same thing at only about 70K. I solved the problem by trading it in on a red 95 the same day. Although I loved the new body style, I have always regretted giving up my black beauty ragtop Debbie

[kc240guy]

hey i know how to fix it and it costs nothing. you see theres a sensor that measures the resistance in the line and makes it shift according to that. cuz its an electronic tranny. theres a second way the car can shift. it just goes by the engine rpm and throttle position which is the better way to do it but it doesnt by default. all you gotta do is pull a sensor plug. its behind the battery a little bit and its the top one. pull it and the car will never do it again. the previous owner did the research and fixed it and told me about it . so far ive helped a couple other people with the info.you will also notice the od on light blinking right after you start it.
Modified by kc240guy at 6:54 PM 6/29/2006

[sudcricket]

Hi,I have a hyundai Elantra 1997 model. and I have a gear shift problem. The problem doesnt happen when the car is cold, but as it runs and temp increases the car wont shift from 15-20-25 mph. as if its stuck and then moves hard. I read the topic on nissan 240 similar problems with many owners and the solution found was "removing the plug from revolution sensor, and the backup speedometer will tell the module when to shift". Is there any such solution for Hyundai Elanta aswell. Please do let me know, you can also e-mail me at simsudra1@yahoo.com.

Thanks,Sudhakar

[tcrow31]

To everyone that posted here, did replacing the Revolution Turbine Sensor fix the shifting problem? I am currently having the same problem. i have no 2nd and 4th gear here is a link to my post. zerothread/197088

[NISTECH]

I read through your post and know it doesnt sound like your rev sensor I think you have something internal going on inside the trans. perhaps wrong fluid or contaminated fluid.

[tcrow31]

It could very well be. I tried unpuging the turbine sensor and it didnt make a change. the only weird thing is that this happened all the sudden with no warning. that morning it shifted fine and i parked for like 2hrs then drove home and at first it was fine then i noticed no 2nd gear and 4th. now im wondering if a silonoid is cloged. i know this section is for the 240s but would you happen to know where to get to the silonoids and where i can download a FSM possibly for free for my car. Did a search and found one for everyone else except mine.

[jamesblonde82]

Well guys I found out something interesting about having your automatic transmission rebuilt. Apparently, when you opt to have your automatic transmission rebuilt, this does not include rebuilding the "valve body" which is the brain of the transmission. Several people have posted on here and on other places on the internet who decided to rebuild their transmissions only to find out that they still had the shift problem. What a bummer to know that you spent all that money for a rebuild and it didn't actually fix the problem.

The valve body has all sorts of control valves and springs and is a very expensive part to replace, which is why most tranny shops don't rebuild or replace these.

I have learned that more than likely I have a stuck control valve in the valve body and the reason that I normally don't have a problem in colder weather (50° or lower) is because there is more pressure being built up in the valve body to compensate for the colder temps. and when it's warmer weather, the pressure isn't as high and therefore one of the control valves that pertains to the 1st to 2nd shift is getting stuck. I was told that an additive called "Transmedic" might unstick this valve. It will take about two to three weeks to really get into the system, but that it might keep that control valve from sticking.

What are your thoughts on this?

240ROCKER

Modified by 240ROCKER at 1:03 PM 3/1/2005

i can vouche for that. i rebuilt my A/T about 6 months ago. it was slippin, shifting slow. then finally the torque converter went out. so i did the whole nine yards. i seen the valve body, made sure it was operating by blowing pressure in it. it shows u how to check in the rebuilt kit manual. basically all i changed was the clutches and rings and what not and of course the torque convertor. so now it drives a LOT better, but it still shifts slow. like the valves are working but not fast enough. this must be a issue with these cars for sure. while doing this, i also found out you can use pathfinder transmissions. so if any of you guys ever just want to swap to a used one, you can use the pathfinder as well. but if you rebuild a pathfinder tranny, make sure you get the parts for the pathfinder, not the 240. the 240 clutches arent as thick. if u put them in a pathfinder tranny, you will have serious shifting probs. and dont ask me how to tell the difference if youre not sure. i found out when mine was completely apart that it has the pathfinder tranny in it by measuring certain internal parts and comparing them to a chart. then i wrote on the tranny for any future reasons, that its a pathfinder tranny. good to know these things.

[jamesblonde82]

hey i know how to fix it and it costs nothing. you see theres a sensor that measures the resistance in the line and makes it shift according to that. cuz its an electronic tranny. theres a second way the car can shift. it just goes by the engine rpm and throttle position which is the better way to do it but it doesnt by default. all you gotta do is pull a sensor plug. its behind the battery a little bit and its the top one. pull it and the car will never do it again. the previous owner did the research and fixed it and told me about it . so far ive helped a couple other people with the info.you will also notice the od on light blinking right after you start it.

Modified by kc240guy at 6:54 PM 6/29/2006

can you be a lot more specific. was it the fuse box? what relay or whatever was is that you pulled?

[kc240guy]

the fuse box behind the battery. there is a set of plugs behind that box. pull the top one.

[Glyph]

This write up is incredible. The amount of cumulative time and money that has been saved by the efforts and diligence of a couple of dedicated Niconauts is staggering. When I first bought mine I too had the exact same problem. Instead of dumping big bucks into it only to receive nothing back but frustration, I found this post, followed it to a tee, and haven't experienced even a hint of the problem in over three months now. THANK YOU guys. You know who you are.

[acidbbg]

good work guys!

Charlie

[Florida240sx]

Been going good now for 3 weeks Too ba dmy engine is toast, and now swapping in a vg30dett

[MNVERT]

my tranny wont shift into any gears when in drive,reverse,etc. anyone had this problem b4?

[tumolt]

I went through the same thing. You're wasting time and money trying to figure what is wrong with your transmission. I went through two repairs only to find out the reason for the intermittent shift was a burned out resistor in my computer. It is located on the passenger side wheel wall behind the plastic cover. It is a mother to get to and you'll see two boxes, one on the bottom and one way up top. The one up top is the computer. You'll have to pull the fan motor (a big feat) but can be done. I left one clip off since it was a mother to put back on. You have to take the cover off of the computer and check to see if there are any burned components. Some companies do sell rebuilt units. Mine came from ACE in Hollywood, Florida at a cost of $150. I wish I knew before going through two rebuilds. It might be a good time to think about that too! Other than that, don't overheat your motor or you'll be going through what I am with a valve job and a mechanic who can't get it to run. These cars are nice but the mechanical problems that come up are no picknic. Good luck. Matt

[MNVERT]

I went through the same thing. You're wasting time and money trying to figure what is wrong with your transmission. I went through two repairs only to find out the reason for the intermittent shift was a burned out resistor in my computer. It is located on the passenger side wheel wall behind the plastic cover. It is a mother to get to and you'll see two boxes, one on the bottom and one way up top. The one up top is the computer. You'll have to pull the fan motor (a big feat) but can be done. I left one clip off since it was a mother to put back on. You have to take the cover off of the computer and check to see if there are any burned components. Some companies do sell rebuilt units. Mine came from ACE in Hollywood, Florida at a cost of $150. I wish I knew before going through two rebuilds. It might be a good time to think about that too! Other than that, don't overheat your motor or you'll be going through what I am with a valve job and a mechanic who can't get it to run. These cars are nice but the mechanical problems that come up are no picknic. Good luck. Matt

thanks for the info i think thats what it is , i just ordered parts for the manual 5speed swap but im gonna try that first to see if it is what u said cause i think it is a electrical problem ill keep u guys posted...

[Pathfinder_1997]

Hey I am new in this forum but this Nico Club is the best Nissan Source on the Net.I have a 1997 Pathfinder LE and I have a problem in the tranny. I start the engine and in about 15 minutes of driving the tranny upshift the overdrive and downshift the overdrive is just do this all the time this lasts months. I want to know if it the revolution sensor have something to do whit this?If have something to do where is it?

THANKS!!

[nosferatu226]

I just bought a 93 240 today and it has the same problems everyone else seems to be having but a little different. It will only shift from first to second at around 6000 rpm, and from second to third at redline. I've only had the car for a few hours now but i havent seen it do anything other than that. I tried removing the revolution sensor (the top plug behind the fuse box?) but it didnt shift at all and the car had much less power. The car also has some other electrical problems that make me think it could be a problem with the wiring harness? The tail lights and brake lights stay on when i turn the car off so I have to disconnect the battery when i turn the car off, the pop-up headlights sometimes stay up but if you press the button to make them go up and down enough times they will eventually go down, also the e-brake light inside the car stays on most of the time but will sometimes go off. I didnt know if any of that stuff might be connected in some way to the transmission screwing up. Maybe i just have a lot of sh*tty wiring? I hate automatics...guess you can't complain when you get a running car for $400 though. If anyone can help that would be nice. Great job on the rest of the thread by the way. Looks like you guys spent alot of time on this.
Modified by nosferatu226 at 10:13 AM 7/17/2007

[aradapilot]

I've been having a problem like this recently...I had the car off the road for a while as my camshaft snapped (yes, snapped in two) and finding another was a pain, and now that I swapped the new one in and went for a drive she wouldnt shift until near redline. It seemed electrical...as the tranny had been fine up until then and a few connectors had to be taken apart to do the timing work, including the tps. When I'm home from work tonight I'll try undoing the rev sensor...hopefully it's that, maybe hurt from sitting not running for a while during a heat wave...you'll hear back from me soon.

And a note, I read this whole thread and it's been immensely helpful - would've taken me forever to test all that by myself. Thanks all! Hopefully this will get linked in a sticky or something as it seems to be a common problem.

[aradapilot]

Okay...same problem with it unclipped (the top connector with 3 prongs next to the relay box, right?). So, trying to figure out what it is. More details:shifts 1-2 at redline. shifts 2-3 at about 5500-6000. haven't gotten to 4 yet, as i'd need to go about 80 to redline it in 3rd and I don't want to go far from home to a nice highway or anything until I work this out...also, when it finally does shift, if i let off the gas the rpms drop down to about 1k even if the engine should be held higher by the trans...not sure whats causing this. I can get back up to a normal range easily and the torque kicks right back in.note: having gears 1,2, and 3 means all solenoids fire. I tried disconnecting the kickdown switch too...no luck there.Could this be a problem with the tps? what other inputs are used? It seems like the rev sensor disconnect worked for everyone but me...though my problem sounds identical.

[nosferatu226]

Okay...same problem with it unclipped (the top connector with 3 prongs next to the relay box, right?). So, trying to figure out what it is. More details:shifts 1-2 at redline. shifts 2-3 at about 5500-6000. haven't gotten to 4 yet, as i'd need to go about 80 to redline it in 3rd.

yeah thats exactly what happens in mine.

[aradapilot]

could be tps or vss...it's going to be hell pulling my atcu out.any other ideas?

[nosferatu226]

I've got it in a shop right now. Hopefully they can figure something out. I'll post it if they do.

[aradapilot]

It's the TPS. was throwing 2.68V at closed throttle as opposed to the 0.4 expected. Just got a replacement, gonna swap it in a little later, I'm tired as hell.Check the voltage on term 20 on the ECU (NOT atcu) to ground, see if it gives 0.4 at closed throttle and 4.0 at open and ranged in between. Sounds like you're having the same problem as me.And driving with the bad tps disconnected was fine. Obviously it shifted based on the charts in the fsm rather than pedal pressure, but otherwise performed beautifully.

[nosferatu226]

thanks for the info, let me know how it turns out

[LushPenguin]

hey man, you're totally correct!!!!

After noticing "rockers" photo I dropped what I was doing, went out ,and unplugged the top plug behind thebattery & fuse box..... That was 3 days ago andI've put almost 80 city miles on my car since thenand it has run perfect!!!!! THIS IS A HUGE DISCOVERY!!!!

YOU ARE SAVING US BIG $$$$$ Give me a few weeksand if this still works I will mail you both a check for$75.00 each.... I wish I could do more but I'm at atransitional stage in my life currently and can't reallyafford much more.... Eitherway I think anyone who's found this to work for their 240 AT'sshould salute you at the minimum and cut youa check or money order for for fixing the problem atzero cost!!!! Again man thanks!!!!!-Dennis "Nframe346@hotmail.com"

[LushPenguin]

I said "rockers" photo but I meant yours!!!! Dude that hastotally repaired my shift problem at zero cost!!!! Bill me if ya'dlike but I prefer to send ya $75.00 in a few weeks when I get paid again... My car was not shifting two or three times in a 5 mile period... I pulled the plug and WOW it runs fine...I've put 80 "city" miles on it in 3 days and it has run flawlessly!!!!

Again thx, -Dennis "Nframe346@hotmail.com"

[nosferatu226]

aradapilot, where is the tps located? you wouldn't happen to have any pictures would you?

[nosferatu226]

ok i got the tps off but i havent had a chance to try it yet because i think my battery is fried...i guess its new battery time

[ishkabibble]

Well, I hated the way my car shifted (seemed to sometimes hesitate for a second before shifting, never wanted to let the car rev up, etc.), so I tried out disconnecting the rotational sensor. Shifts much better now, so I'm leaving it that way.

[nosferatu226]

ok so i got the tps unplugged and the car started but i'm still having the same problem...no shift until redline. anyone have any other ideas?