[offroaderdodge]

Hello everybody,new to the forum.
just bought a 2001 pt cruiser,with a transmission issue.
will go in reverse like nothing is wrong,neutral i normal,but drive seems like trans is locked up and engine stalls.
anybody experienced in this matter?
i am a licenced tech,familiar with most inner workings,but this issue has me a little stumped.

any suggestions would be appreciated.
thanks in advance.
Frank

 

[ImperialCrown]

It sounds mechanical or hydraulic. The TCM fault codes (if any) may need to be read with a more advanced scan tool than a generic engine code reader.
There are hydraulic pressure taps across the front of the case underneath the solenoid pack for more diagnostics. See what is applied when it shouldn't be.
It sounds like an internal leakage or blocked valve body vent may be applying the lock-up converter clutch when it shouldn't?
If the vehicle is already rolling forward when dropped into gear, does it still stall?
Has the pan come down for a look? Use ATF+4 only.
http://www.scribd.com/doc/93730784/41TE
http://www.shinseiauto.com/japanese/transtar/42rle.pdf

 

[offroaderdodge]

i can bring it to a stop ,once it stops,it behaves -i cant say normal as running with wheels in the air makes things behave different than on the ground.
i didnt want to drop fluid ,for one getting mopar atf+4 is a challenge in itself.

seems like its not in limp-in as it seems to shift from low and through the gears.
its like the lock up is engaged without a command.

may drop pan this week,and clean valve body.perhaps i should wait for the real service manual...

i seem to have a little trouble with this forum,i mispaced the original thread,and posted another,i will attemt to remove it to keep things sorted.

getting the hang of it now,methinks.

 

[Doug D]

First thing to do is retrieve any transmission fault codes. You'll probably need to take it to a dealer or reputable transmission shop. Most of the code readers can only get the engine codes and not the transmission codes. You will probably have to pay for this service, but it will be well worth it. Otherwise you'll just be guessing as to the problem. Make sure the fluid is at the proper leve to prevent slipping. Has the fluid/filter ever been changed?

 

[offroaderdodge]

havent owned the car for a week,history of trans is unknown,has 112,000 km's on it,im sure fluid hasnt been changed.its in the plan,if i get it working.once i prove its either electronic or hydraulic issue,then maybe get it working.trans service after that.

chasing wiring today,when manual shows up will test solenoid pack to make sure new one isnt bad.then pcm.

 

[offroaderdodge]

Pulled apart all the connectors ,found moisture in most of them.no green corrosion anywhere. Wires all seem good. Rescanned after running it. P0731 came up in transmission pending codes. First gear incorrect ratio.

Speed sensor above solenoid pack was clean output sensor had a little metallic pudding on it.
Got wheels to stop in D,after 30 seconds it stalled.

 

[TWX]

Well, this is entirely anecdotal as they're different implementations of automatic transmission, but when the lockup clutch on my '78 Chrysler Cordoba stuck engaged, when stopping it behaved like a manual transmission without pushing in the clutch. I had to shift to neutral when coming to a stop and I had to apply throttle and rev the engine up before shifting into drive to get moving again.

Once it's started malfunctioning, if you restart it and try driving and it exhibits behavior like what I experienced, then I would expect that it's the torque converter or whatever can cause it to engage.

 

[offroaderdodge]

reverse is normal,could drive it around backwards all day.so,i would say not the torque convertor.
the typical failures of the 727 was broken nose on torque convertor and breaking bands.
easiest on the planet to repair.
i miss them good ol days...

 

[offroaderdodge]

update-
replaced input and output speed sensors,filter and fluid.
cleared code and restarted vehicle.
still shifts into second,
p0731 is gone,now p0755 came up.
this is getting a little frustrating,waiting for manual so i can trace every circuit an prove wiring is 100%
pan was clean,a little metallic debris on magnet.
3 tiny looks like brass pieces,but no significant pieces.

going to warm it up good,make sure its properly filled ,disconnect battery and retry.
maybe it needs a drive?

 

[ImperialCrown]

Unless you had codes specifically for the input and output speed sensors, I would have held off replacing them. Your old ones are likely still good.
P0755 is the 2/4 solenoid circuit fault code. Don't automatically replace the solenoid pack for this code as it is usually caused by something else. Start with a 'Possible Causes' list to find out what you can narrow it down to by the process of elimination.
Erase the code and see if it comes back. If it does, then it may be real. If not and some other code shows up again, then see if that code may be real. Going into limp-in (2nd gear), the TCM may set a code for whatever it was in the middle of doing at the time.
I'm sure that who ever had this car before went through trying to fix it until it was decided that the problem meant a rebuild. This isn't to say that you shouldn't double-check their work and get your own diagnosis.
I hope that your manual comes soon. There is some diagnostics in the post #2 links that you can use to get closer to the real problem. Diagnose first.

 

[offroaderdodge]

i suspect the hole in the wall garage that did the previous work didnt have the diagnostic tools ,manuals or patience to see this through.
priced rebuilt trans at 2500.00 installed i bet in the hopes owner would give up on it or take it elsewhere.
my attempt at backyard diagnostics has just hit a wall.
now with my shiny new oem manual i now have the wiring diagrams,component locations and a little info for troubleshooting.
discovered the wiring i was chasing and connectors i was checking werent all that i needed to find.
found the tcm is located in left front fender,which in all my internet research it was mever mentioned.
heading out to dig into some more wiring.

so i pulled fender liner,trans controller is in deplorable condition,box has corroded to the point where it has a hole through the aluminum.
i was going to post a picture but it no workie.
i was hoping to pull the cover on trans controller and look inside,but i'm sure i will destroy it if i try to get the screws out.
i'd like to think this is the issue,but wont know til i replace it.

 

[offroaderdodge]

Ok,the plot sickens.

i decided im replacing the tcm before i proceed any further,as well as checking all the wiring.
so peeled cover off tcm to see how bad its corroded.
pretty much falling apart, and the gel inside is breaking down.i comfortable with the decision to put in another tcm.
will let you all know in a couple days if my haphazard diagnostics are on the mark.
used tcm has got to be better than what i have,and for 50 bucks its worth a shot.

 

[offroaderdodge]

***SOLVED!!!***
trans controller was hooped.
installed a used controller,fired it up and all gears working.no trans codes no stalling.
so to sum it up
input and output sensors -100.00
haynes manual- 30.00 waste of money
oe service manual-70.00
used trans controller -30.00
trans fluid and filter 50.00

280.00 well spent considering the shop wanted 2500 for trans rebuild,and would NOT have fixed it

Thanks for all your help.