91 transmission SHIFT PROBLEM

ONLY for ADVANCED technical discussion about the 240sx!
FIA28950
Posts: 12
Joined: Wed Jun 28, 2006 5:15 pm
Car: 1991 240SX SE

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HEY GUYS

please go to the bottom of this post for my latest problems.thanks,paul cass

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

Modified by FIA28950 at 6:18 PM 7/27/2006
Modified by FIA28950 at 6:19 PM 7/27/2006


180fan
Posts: 7799
Joined: Sat Dec 14, 2002 12:16 pm
Car: 89 fastback

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Poke around for loose connectors if it's intermittent.

BreedOfSpawn
Posts: 74
Joined: Mon Jun 26, 2006 4:55 am
Car: 1993 Nissan 240SX

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Check your modules biggest problems with auto transmission's. My daylight running module burned out and took out my wiring and messed up my transmission bad on my previous car. A few new modules and a some new wires and she was running perfect again.

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jdm_master_X
Posts: 3518
Joined: Sat Jul 23, 2005 6:22 pm
Car: 92 Nissan 180SX LHD!...LaWL
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it is probably an intermittent problem with connectors to command the AT to shift into its proper gearing. a defective vacuum modulator/governor can also be a reason if its intermittent, but its the last thing to suspect in a problem like this.

should the electrical be okay, check the vacuum lines to the AT to see they are all okay and getting the right amount of pressure to switch start in first gear and not bypass it.

worst case scenario is the lip seals in the clutch pack is bad and is not holding pressure to allow the shift. and the worm tracks in the valve body could be gunked up causing it not to shift properly.

FIA28950
Posts: 12
Joined: Wed Jun 28, 2006 5:15 pm
Car: 1991 240SX SE

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hey guysgot the car back from nissan and they drained and flushed the system and then ran a systems check. solonoids checked out ok. test drove the car and everything worked just fine. i've been driving it around and so for the transmission shifts fine. i'll have it for another week before i take it back to my daughter so if its going to act up that should be enough time to do it. if not then i guess the flush and new fluid did the trick. thanks for the help.paul

FIA28950
Posts: 12
Joined: Wed Jun 28, 2006 5:15 pm
Car: 1991 240SX SE

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ok guysguess it was a good thing i kept the car for a while. yesterday the transmission peoblem and ac problem resurfaced. today it happened agian. the transmission problem can be corrected by turning the key off. when i restart the car the problem is gone. the same thing seems to work for the ac. however, sometimes i have to wiggle the fan switch before the compressor engages. before these two problems surfaced my daughter had the ignition switch replaced by nissan. it may not be related, but everything worked before the switch was replaced. today when the problem reoccurred i drove directly to nissan and had them run a scan. the scan showed three things. a knock sensor, at com, and cool temp. i told the tech to turn off the car and restart and that i would bet that the transmission would now shift perfectly. turned the engine off and restarted and the transmission and ac worked perfectly. ran a scan and it came back with the knck sensor and cool temp. turned it off and restarted and the only code was the knock sensor. the tech said that the tcu module needed to be replaced. $640 plus labor. he thinks that the ac problem is with one or both of 2 inline seonsors. last week i paid $275 for a transmission service that in effect did not do any good. i guess my question is if the tech's diagnosis to solve the problem is correct- number one, and number two-what would happen if the transmission module is left alone. for now it seems that by turning off the engine and restarting the engine the problem is at least temporalily solved. the ac is another question. as my daughter is on a budget this is getting to be a pricey fix. if the module needs to be replaced is there anwhere to purchase one that is not so expensive? where is it located? thanks for any help.paul cass

FIA28950
Posts: 12
Joined: Wed Jun 28, 2006 5:15 pm
Car: 1991 240SX SE

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btt

nuknght
Posts: 9
Joined: Fri Dec 23, 2005 5:25 pm
Car: 1991 nissan 240sx w/ ka24de

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inexpensive used nissan partswell at least they were until i post this, then the prices are gonna skyrocket and/or become relatively impossible to obtain. Somebody at least save me a new shifter for an 91 AT transmission and an inside driver side door handle. Please!!!!!!!!!maybe even a fuel pump too-----car is having fuel issue due to the nasty hot weather here in Montana.

Felton Auto PartsSeattle, WA1-800-713-3999

"I am sitting on a gold mine (with this number) and now...? I guess I'll have to wait and see what happens."


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