1992 240 SX Convertible - Auto Trans. stays in 3rd gear.

[09quickly]

I have been reading up on some of the other automatic transmission issues addressed by NISTECH folks, hoping it would correct my problem as well, but so far, no luck. I have been reading the thread posted by some of you guys and NISTECH regarding intermittent shifts between 1st and 2nd gear (It sounds like I need 240Rocks as my neighbor). I tried all of the electrical sensor disconnects suggested in the thread, but still no luck. My specific problem is that the trans shifter goes into R, D and 2, but will not go into 1. Also, the trans will not upshift or downshift, only stays in third gear. I disconnected, cleaned, left disconnected, and re-connected all of the sensors mentioned in the other thread (Revolutions Sensor, Speed Sensor -found by accident, as well as several others located in the general area of the fuse box.) Still no luck. Everything is a little cleaner, but still no shifting. My next thought is to drop the pan and address solenoids and the valve body, but I'm a remove and replace kind of guy, very little diagnostic know how. If someone is familiar with this issue, please steer me in the right direction. 09quickly.

[NISTECH]

In this case your going to have to diagnose to figure out what needs to be replaced. Your trans is in 3rd gear failsafe. Meaning it is seeing something from a sensor incorrect so it has no idea what gear to put the trans in. There was a proceedure posted in that thread I believe that tells you how to put the trans into diagnostic mode with the OD button. When it goes into that mode start counting the flashes of the light. This wil give you a code. Once you have that code post back and I will look it up in my manual.

[09quickly]

Thanks, I remember the other thread saying something about the o/d light flashing 8 times. Mine flashes so fast I can hardly count them, but I am going to estimate it is around 15 times. I will check it later tonight or tomorrow and let you know. 09quickly.

[NISTECH]

no when it flashes when your turn the key on that is not a code it is mearly to let you know there is a code and something is not reading right. You need to activate it by pushing the OD button so many times while holding the break pedal and keeping your tongue at just the right angle,, you get the idea.

[09quickly]

Gotcha - When I double checked the manual, it said 8 seconds of flashing, not 8 flashes. That is about what it is doing now. I will wait until tomorrow evening when I can steal my wife's garage space to look at it more thoroughly. Also, the manual I have access to (91-94 Nissan 240 SX on CD) refers to a "CONSULT" tester. Am I headed in that direction? Thanks for the guidance. 09quickly.

[CDE]

I remember that OD test.

As nistech stated it's a little bit fussy and quite a few steps to get the right things in the right place at the right time....

I would search for you but haven't got the time right now....between school, work and fiance I have no life :|

[NISTECH]

Yea your going in the right direction but do the "without consult" test.

[09quickly]

Sorry about the delay, but work has been getting in the way of my private life and it is really starting to piss me off. I touched base with CDE from the other transmission related thread, but he could not recall the proper sequence for the o/d button diagnosis because his speedo did not work. Nissan was as useless as tits on bull, saying there is no way to diagnose it without their computer. My next attempt will be an e-mail to 240rocks, he seemed very knowledgeable about these things. Minor detail, if I find out how to conduct the self diagnosis with the o/d button sequence , where will the the code "read out"? 09quickly.

[NISTECH]

Ok AT self diagnostics comin at ya. Start by holding your tongue so it hangs out the left side of your mouth, raise your right eyebrow. lift your left leg off the seat.

1)start vehicle and warm it to operating temp.2) turn the key off and press the OD button to on position make sure shifter is in park.3)Turn the key on engine not running make sure the od light comes on for 2 seconds. If it does go to #4 if not post back.4) turn the key off and shift the trans to D. use the lock release if neccesary. Set the OD switch to off.5) turn the key on and wait at least 2 seconds. then set OD switch to on.6) Shift to 17) set overdrive switch to off.8) press accelerator to floor then release it completly 9) set overdrive switch to on.

This will start the OD light to flash your codes. The light will have one long illumination flash then start flashing short blips. Watch the flashes carfully cause one or more of them will stay on slightly longer then the others. There are 10 flashes total. If say it goes like this, first the start signal long flash then blip..blip..blink.blip..blip..blip..blip..blip..blip..blip. notice how the thrid was a little longer. The would be a 3 which corrospondes to TPS short or open.

When you do it there are 10 posibilities plus a no failure which would be all blips of the light. post back what you have and I can reffrence my manual to see what it is.

Reffrence is a 1992 240sx service manual.

[09quickly]

Thanks, I might actually get a chance to do this tonight.09quickly

[09quickly]

AT Diagnostic test finally attempted on Sunday 10/30-Thanks for the info. I drove around the block a few times in 3rd gear to get it to operating temperature. Steps 1 through 5 went like a dream, O/D light came on for 2 seconds as described, in Step #3 and Step #5, then went into rapid flashing for 8 seconds. Step #6 is a no-go. Shifter will not go down into 1, will only go as far as 2, then binds. Pulling on shifter with force puts the red indicator in 1, but it will not physically move any rods into the desired position. The rest of the sequence could not be completed in 2, that's where I stopped. 09quickly

[NISTECH]

You gotta figure out whats causeing it to bind. put the car in park and crawl underneath and disconnect the rod from the trans. Then move the lever on the trans by hand [ make sure the ebrake is set dont want the car rolling over you when you pull it out of park] conte the clicks it makes at the trans. it should make 5 clicks frompark position. park itself is not counted. If it stops at 4 and wont make a fifth you have a problem with the inhibit switch or the valve is jamming in the trans.

[09quickly]

Finally able to crawl under the car on Sat. 11/05. Cotter pin holding the shift linkage to the shift lever on theside of the trans. was binding on a small, bolt-on shield that appears to route some wiring from the engine to the trans. Anyway, I removed the linkage arm and tightened the cotter pin so that it is more snug against the lever and the linkage. I now have 5 positions in the lever as indicated. Went through the diagnostics you provided, and as in your example, 3rd light flash after the long illuminated flash at the start was longer than rest. Did the sequence three times to be sure. When you get a chance to post back, please tell me where the part, connector, whatever it may be, is located. Thanks millions for your help so far,even though the whole car will need much more work, I am looking forward to it. this has been interesting as hell (I guess because it hasn't been real expensive yet) 09quickly

[NISTECH]

That indicates your TPS is disconnected or shorted. Now the ECM also looks at the TPS so you need to pull codes from the ECM to see if it is also storing a code for tps since they both use the same circuit. If it doesnt this will indicate the harness between the ECU and AT control unit has a problem. If the ECM DOES have a code stored for it then your problem lies with the TPS. The tps is the gray connector hanging off the TPS not the black one plugged directly into it.

[09quickly]

I assume by TPS you mean the throttle position sensor, and by ECM, you mean the ECCU (I read my manual every now and again). More questions. Is the TPS located at the business end of the air intake tube, with the hose clamps, on end of intake manifold at front of engine? Is the ECM located behind the kick panel on the passenger side below the dash? If so, I found that as well. How to read codes? 09quickly

[NISTECH]

Yep on both. Goto http://www.240sx.org and scroll down the FAQ list till your get to engine code reading for your appropriate engine.

[09quickly]

10-4. I went to the "search" icon and entered all of the possibles for "TPS" and "ECM", but did not try the FAQ icon. Other issues: This car needs many little things, hopefully nothing that I can't do myself (with your guidance). I recently bought this car for $900.00, so I don't know alot of its' history. Anyway, other items that need to be tackled:

1) Oil pan gasket - In following the instructions for oil pan gasket replacement in the manual, it says to drop the front suspension cross member to get access to the pan. The motor mounts are on this cross member, not on the frame. Do I need to support the engine in some fashion before dropping this cross member on my head? Also, while I have the pan off, will the crankshaft seals be easily accessed to replace them at the same time as well? (Lying on my back with the car on jack stands, front only). Also, the oil pan took a hit somewhere along the line and is sporting a decent dent on the front (more than likely the source of my leak). I want to replace it, but cannot find anyone who lists a replacement pan (OEM). Any suggestions?

2) Remote gas door and trunk release lever - I pulled the driver's seat out and gained access to this lever. The cable had come off of the lever mechanism completely. I can not figure out, without a picture, how to re-attach the cable. Can you hook a brother up?

[NISTECH]

What are your engine codes if any?

If possible just bang the pan back out and flatten the matting surface with the engine so its even. There is no gasket for nissan oil pans just use silicone sealer. I know aftermarket places sell gaskets but the factory uses no gasket.

I have the same yr and model 240 if I get a chance I will snap a shot for ya.

[09quickly]

I found the codes for the ECM where you suggested, and I may get a chance to look at it tonight after work, 9:00 p.m. or so (EST). What about my issue regarding support for the engine when I drop the front suspension assembly to access the oil pan? Do I need to figure out a way to suspend the engine, via an engine hoist or some other rig? Or will the engine stay in place? It doesn't look too inviting underneath there as I start loosening crossmembers. 09quickly.

[NISTECH]

Eww yea sorry about that. Yes you need to either get an engine support cross bar that stratles the engine bay and rests on the strut tower area near the fender. A hook would be attached to the eye at the front of the engine. The alternative is to use a cherry picker to hold the engine up while doin the pan.

[09quickly]

O.K. codes - 3 long and 3 short=Exhaust gas O2 sensor circuit. Part II with the engine on. Check Engine light came on almost once per second when test first started, slowed to one long light every ten seconds. What up? Does this point to the A/T control unit since it did not reflect the code for the TPS (43)? 09quickly.

[NISTECH]

No other codes came up? after it flashed the egr code 3 times?

[09quickly]

Nope, 3 long, 3 short, I watched that sequence about a dozen times to be sure. Same thing at the engine warning light. During the engine running portion, the engine light came on for long and short flashes, but they were long, long, long, short, short, long, short (no apparent sequence). 09quickly.

[NISTECH]

Yea that is just mixture/O2 readings. This isnt good then. You are going to have to start probing wires at the TCM to check for voltages and such from the tps. Since the ECM doesnt see the TPS failure it means your problem is likely between the ECM and TCM. I will need to pull some diagrams for the system and post them as well as where to probe the connector for checks.

[09quickly]

Sounds ugly. I guess I will have to break down and by a voltage test meter. 09quickly

[NISTECH]

Give me some time to do comparisons of my service manual for my 92 against my 93-94 manual I have on disc. I will be posting the 93-94 manual info because my 92 manual is a book and not feasable to load to the comp. I have to cross reffrence wires to see if they are the same and adjust if neccesary in the 93 information to match a 92.

[09quickly]

That sounds an awful lot like work. I hate when that happens. Thanks for your patience and diligence, they will most likely go unrewarded, as in most cases. Post back when you can, I am going to concentrate on my oil pan gasket issue while you hit the books. 09quickly

[09quickly]

Re-did the diagnosis tonight, but all I got was 55's. I guess I dumped the old codes last night. I thought starting and re-starting a few times would show the old mal-function codes if they are still valid? I know I didn't fix anything! 09quickly

[NISTECH]

After you erase the codes they will not come back untill it sees the failure occur, EGR failure does not show till it is driven under part throttle operation for awhile.

[NISTECH]

Ok in this diagram you will be testing the 3 terminals indicated in the drawing. wire colors at the terminals are as follows. If the wire color doesnt match as your looking at it perhaps you are looking at the connector upside down.here's the colors match and then test . If they dont match do not assume it is a fluke you are looking at it wrong I garuntee it.31= light green with red tracer stripe34= white with blue tracer stripe35= black

on terminal 31 you should see a constant 5 voltson terminal 35 you should see a constant voltage reading of less then .2 voltson terminal 34 you should see about .5volts at idle and a varying voltage when you apply the throttle to above 4 volts at wide open throttle.

This test is done with the key in the on position but the car NOT running.Also the A/T control unit will be plugged in your will be back probing the terminals.

The A/T control unit is locate on the passenger kick panel area next to your heater box. May need to remove the glove box assembly to gain access to it.