Strange Transmission issues- 99 rodeo

Hello-
I'm the original owner of 1999 Rodeo 3.2, auto trans, 2wd w/ 76k miles.
For about 3 weeks I've had a very rough thump when the tranny shifts (usually from 2nd to 3rd gear)- but only occasionally. After the 2nd incident I had a Transmission Drain and Fill done at my usual mechanic. No problems were found.
Also during one of the occasions, I tried to shift manually through the gears, but the tranny shifted through all gears while selector was in L ???!!!
I've since noticed that this tends to happen when I start the car with wipers left on from previous drive. Could be just a coincidence- but it's happend twice now.

ANy clues??? Hints??? (other than don't start with wipers on)

Thanks in advance

Check out the FAQs, particularly the faulty transmission range sensor section:

http://isuzufaq.ibctech.ca/#faq59

that FAQ# has a link to a real good pdf write-up with excellent photo's.

i'm also going to suggest this link to my posts at 4x4wire:
http://www.4x4wire.com/forums/showflat.php?Cat=&Number=902938&page=2&view=collapsed&sb=5&o=93&fpart=1
"92 trooper AT harsh up-shifting 2nd to 3rd only"


i'm in the middle of figuring this out for my 1992 trooper, and i give alot of symptoms i'm experiencing that will probably confirm what's happening with you. . .

. . .plus it has a number of other good links that can help to confirm this diagnosis, and whether you want to try the clean and put back on option.

hth


edit.P.S. I tried to shift manually through the gears, but the tranny shifted through all gears while selector was in L ???!!!
for the life of me, i can't figure out what you're saying here. will you clarify? do you mean when you shifted manually to L and drove that the AT progressed thru the gears as if in Drive D ? Or?

edit.P.S.
for the life of me, i can't figure out what you're saying here. will you clarify? do you mean when you shifted manually to L and drove that the AT progressed thru the gears as if in Drive D ? Or?[/quote]

Yes I mean that I manually put the selector in L, and as I drove- the transmission shifted as if it were in D. Crazy huh?

I think I will try the cleaning this weekend- wish me luck

It sounds like your range mode sensor needs a cleaning, as it doesn't know what gear it's in.

Yes I mean that I manually put the selector in L, and as I drove- the transmission shifted as if it were in D. Crazy huh?well while i haven't read that one specifically as a symptom, it seems likely, considering the harsh 2-3 upshifting, that the range sensor/switch could be the culprit for this too.

I think I will try the cleaning this weekend- wish me luckluck.


bc