ok so my neon is a 2000 automatic and i bought it had it a week and it it started revving to 4000 rpms and would not go past 25 30mph. so i pulled the trans pan and changed the fluid. the fluid was still pinkish red with no burnt smell and looked pretty good. after pulling the pan there was a bunch of gook on the pan and on the magnet which i am in be leave it was breakdown materiel. so i cleaned the pan really good sprayed down the trans with cleaner and replaced the filter and gasket, now when you drive it and you hammer om the gas once and a blue moon it will seem like its slipping going into second gear. not always just once in a while then when you come to a stop the cars rpms start to drop to 500 400 rpms and stalls occasionally and vibrates badly it does that not often maybe 2 times outta 10 stops. but if it starts to do it and you stick it in second gear it goes away immediately. and if you put it back in drive right after u put it in 2nd gear it will sit there and idle at 900 1000 rpms like its supposed to, there's no check engine light and no trans are engine codes when scanned. not sure if its the valve body trans torque solenoid im lost please help it runs thrw all the gears now just haveing that problem when comeing to stop signs are red lights

 

possible sticking lock up valve in the valve body that controls torqu convertor

 

what should i use to clean it

 

will require you to remove valve body , so you'd want to be sure thats what it is.

try some lucas trans treatment in the gearbox first
this is the stuff
http://lucasoil.hodgsoncorp.com/slip...ansmission.htm

 

OK so i used the gear oil like you stated when i changed the fluid and the filter. no change drove it about 140 miles since. so i pulled the valve body out and tore it apart put it back together what i saw was the sensor for the torque converter clutch the one that throws the p0743 code was clogged with gook. 3 of the many valve ***** were filthy slimy so i cleaned all them and stuck them back where i got them. stuck everything back together. now i only have park neutral reverse and drive. 2nd gear yo have to hold it in in order for it to run is second are it kicks it back to drove and cant manually stick it in first. the cables not interrupted either. also occasionally if you stop at a hill and you give it gas it sometime takes 1800-2000 rpms to get it to start up the hill once it starts up the hill it takes off. and other times it dosent have a problem goes like its supposed to. also the problem with it bucking down to 4 5 hundred rpms and stalling it hasn't done that at all since pulling it apart just the going up hills and not being able to stick it in 2nd are 1st gear without manually holding it there. like i said though in drive all gears work just sometimes not so great at start off on hills also there was a plastic round cartage type thing in the middle of the valve body that thing was brown and could barely see threw it so i cleaned that and it was white and could see threw it could

 

wow in 6 hours you did all that?
sticking manual valve?

do you have acess to a scanner to see if the range selector is seeing proper gear
or to see if the PNP switch is working

 

no all i have is one of the little hand held one the shop i used to work at had one but i moved to a new area and no no garage around here

 

whats pnp

 

ok i found out what pnp is park switch is woking if you stick it in gear and try to start it it wont start it has to be in neutral are park also as far as gearing goes gearing is in the right place if i put it in drive i can run it up to 80 with a prob if i put it in second and hold it therei can go to about 40 befor its reving out pretty good

 

i changed the fluid and filter prior to to posting on here thats when i used the lucas before i posted