Trouble with Automatic

[Rusty92MU]

hello everyone im currently trying to work out what wrong with my auto..ok i use to own a 99 rodeo with the 2.8 manual now that doing 110kph use to sit on 3150 rpm now my 92 mu 2.8 auto sits on 3200rpm at 80kph its like it wont change into another gear for some reason?? im not sure if the auto box has a vacume line iv not hooked up... or maybe something electrical.. i have recently dropped my new 2nd hand 2.8 engine in and that why im thinking something i havent connected somthing, now it does rev lots going up hill and its quite sluggish aswell compared to my rodeo i use to own. Am i expecting to much from it or is there something not right?? oh and i did have overdrive on so its not cause i didnt have the button in lol

[geeves]

sounds like its not going into 4th or the lock up converter isnt engageing. Was this auto in the car when you got it and did the engine come out of an auto?
My money is on a temp sender or similar as the computer for the auto takes throttle and temp info from the engine. There should be a sensor on the back of the fuel pump and an extra sensor in the thermostat housing.

[bonkers]

Hey there, Geeves is on the right track. another one to check is the TPS sensor check the post "Auto kicks down way too soon" for more info.. Also be a good idea to install a transmission cooler. i to have an auto and have had it overheat several times when towing.

[Rusty92MU]

Thanks geeves ill get my mechanical mate to check all that out also im not to sure on wether the motor was out of an auto or manual

[Rusty92MU]

Hey there, Geeves is on the right track. another one to check is the TPS sensor check the post "Auto kicks down way too soon" for more info.. Also be a good idea to install a transmission cooler. i to have an auto and have had it overheat several times when towing.

yea i had a read of that thread was very interesting i have a few things im going to check out and iv all ready installed a transcooler because my radiator is nearly stuffed i need to save for a new one... i really want to just convert my mu to manual be so much easier

[bonkers]

I agree a manual is better but manuals still have problems with clutchs, synchros gears etc....and is a costly conversion..

[Rusty92MU]

I agree a manual is better but manuals still have problems with clutchs, synchros gears etc....and is a costly conversion..

yea it is costly i just got a quote for a whole conversion kit for 1600 and im thinking of taking it but i want to sell my auto first but im guessing it will be hard seeming as no one wants an auto.....

[bonkers]

hehe very true.....i would take it if you lived down this way...but no will will pay much for them...$1600 is actually pretty good but im assuming that is old clutch and fly wheel..??

[Rusty92MU]

ok im getting somewere with this problem i think.... iv just unscrewed the sensor out of the thermastat housing and replaced it with the one out of the original motor and took it for i drive and it changed in to overdrive it was wonderful but after a while it stoped changing to overdrive and since this morning after i changed the sensor its only changed up twice..... perhaps my other sensor is crook to?? iv ordered two replacment sensors to replce the two in the thermostat to see if that what it is i also checked fluid level its ok im using the right auto oil i hope. Its what the guy at the mechanics told me to use and he checked it in his book... any more ideas incase its not sensors??

[timster]

My 3.1 Mu had these spells where it wouldn't swap gears to go above 80km.
When it happened, I accidently turned the fan blower off, and it started swapping the gears.
Everytime time it happened I just turned the fan blower off.

[bonkers]

fan blower....??? as in the heater fan??? the auto fluid should be dexron 3.

[bonkers]

does anyone know the parts numbers for the transmission filters or service kit..ill need to get some numbers off my box.

[Rusty92MU]

problem solved: changed sensors over from old thermostat, rotated TPS sensor, changed oil and away she goes:D