• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

aw4 help!! no reverse, no neutral,feels like its loading in park???

scully

scully

NAXJA Forum User
Location
ma/nh border
anyone had this before? i found a thread, but no solution.
heres what i have.
90 mj, 4.0, 2wd.
heres the problem.
park feels like its loading, and doesnt idle free, as if i was in drive but stopped.if that makes sense.
reverse is exactly the same, even shifting back and forth makes no difference in rpm's.
neutral thrue 1st feels like its in second or third with no difference in rpm when shifting, even from park all the way to 1st.
heres what ive tried.
added fluid, way low:nono:, previous owner neglected it a little. no difference.
checked fuse at tcu. fuse was good
checked power at fuse. good
checked power at ecu. good
swapped tcu with a known functioning one, no difference.
any ideas???
i just picked it up for $350 and this is the last problem im tracking down on it.
any ideas would be really appreciated and ill pass on my fix when i find it.
 
TPS doesn't come into play in reverse. A few thoughts come to mind. Try disconnecting the shifter cable at the tranny and shift it by hand. That might tell you if its just a badly misadjusted shift cable. With the shifter in park, is it actually in park and doesn't roll?
You might try pulling the fuse just to see if it makes any difference. Make sure you do have enough fluid in there and maybe peek at the tranny cooler lines to make sure they aren't smushed.
 
x2 on disconnecting the cable and shifting by hand, sounds like the vlves in your valve body arent engaging correctly. if that doesnt work your next step would be dropping the pan and inspecting it for pieces of metal.... which would be bad.
 
winterbeater said:
Many transmission probelms are traced to the TPS. That can be checked with a voltmeter.

When in park or neutral, what happens if you rev it?
Click to expand...
it feels like park, but doesnt seem to rev as freely as my xj.
and reverse feels exactley the same.
it does not move the truck in reverse, but locks the tires like park instead.
and tomorrow after work ill start with the voltmeter.
grrrr i want my mj.
 
lawsoncl said:
TPS doesn't come into play in reverse. A few thoughts come to mind. Try disconnecting the shifter cable at the tranny and shift it by hand. That might tell you if its just a badly misadjusted shift cable. With the shifter in park, is it actually in park and doesn't roll?
You might try pulling the fuse just to see if it makes any difference. Make sure you do have enough fluid in there and maybe peek at the tranny cooler lines to make sure they aren't smushed.
Click to expand...


i pulled the fuse, no difference.
park is park. as in it does not roll, but idles like your on the brakes at a stoplite in drive.reverse does the same.
all other gears are either 2nd or third,maybe 4th.
i havent driven it normal yet and my xj is an ax15, and the parts xj i have i never have taken it on the street, so i have no comparison.
ill check the lines more tomorrow, after work.
fluid seemed ok, but it may have settled so ill check again
 
Mr. mud said:
x2 on disconnecting the cable and shifting by hand, sounds like the vlves in your valve body arent engaging correctly. if that doesnt work your next step would be dropping the pan and inspecting it for pieces of metal.... which would be bad.
Click to expand...

thanks for all the help!!!
ill try all your ideas tomorrow nite and post up.
well at least i get some quality time with the new girl, ms mj:spin1:
 
btw previous owner said his mechanic said the linkage was off a little.
i imagine that would be an easy fix worth doing on the spot....
so im wondering if he pulled that out of his ass, because i imagine he would have probably fixed it.
i didnt woory too much because for $350 and only 120 on the clock AND
it came up from florida 3 years ago.
i was just happy to see threads on all the bolts on the underside.. almost ZERO rust!!!!:yelclap:
 
Check/adjust the shifting mechanism, for sure.

Ok, what type of fluid did you add, and what kind of fluid did the PO/mechanic put in it?
 
shifting mechanism was ok. manually shifted and did the same.
topped off fluid with dextron II.
same results but i noticed it does not rev past 2 grand or so in park and reverse positions... 1st thru neutral revs fine, with neutral acting the same as 1st thru 3rd.
sounds like its defaulting to fourth, but why? mt tcu is fine and sending power, but the tranny is not receiving signal?
am i missing something?
 
Thought it should be Dextron III.
 
Your right.

So, shift linkage, NSS (shift linkage and manual valve input to TCU), throttle body cable, correct fluid, correct fluid level, TPS, TCU, and the Brake Application switch are all tested and adjusted/replaced, so what is left?
 
i have to look up how the tranny actually shifts.
i remember something about solenoids firing to change gears, maybe the input isnt getting to the solenoids and its defaulting to fourth?
but would reverse default to fourth also?
and why cant i freely rev in park or reverse?
 
The solenoids act on the valve body.
 
ok. just finished with the harness testing.
every thing checked out, EXCEPT
c9 position read no voltage when in drive, only read voltage in 2/3
and im still trying to figure out why it seems to be under load in park, and wont rev freely, only to about 2 grand or so.(no tach)
im thinking its all related to some kind of component failure after the tcu.
if one solenoid fails, do they all default? are they in line?
:dunno:
 
You must log in or register to reply here.

Similar threads

L
AW4 will not shift into 1/2, No Reverse
Replies
6
Views
1K
Ecomike
Ecomike
FernGreen
Aw4 Transmission Delayed Engagement
Replies
1
Views
1K
lawsoncl
L
B
Jeeper needs Help !!
2
Replies
22
Views
3K
denverd1
denverd1
S
'88 Temp Gauge Stuck At MAX, Even When Engine isn't Running.
Replies
2
Views
1K
Saudade
Saudade
M
AW4 no reverse, slipping in drive
Replies
2
Views
883
lawsoncl
L
Back
Top