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Discussion Starter #1
When I throw the transmission in neutral (say, coasting down a hill - 4R70W), it'll click into neutral, and then the engine RPMs will keep on going up even if i'm not on the gas, and then start to drop off

eg, if I'm goin about 50 and throw it in neutral, the engine will go from 2000RPM to about 3000RPM and then begin to slowly drop off.

Is that a problem or normal reaction?
 

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it is probably from when the tranny was changing gears it either did the same thing a clutch would do when it it engaged underload.....the energy from the engine doesnt release immediatly.....the rpm has to come down. so when you put it in neutral the power the engine is making doesnt immediatly go away and before it can the tranny goes to neutral and the engine is still trying to keep up with the gear...make n e sense?
 

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i agree,.....you figure,.....if it's travelling @ 2000RPM under load,...when you release the load the engine is still spinning quick enough to move the now non-existant load at 2000RPM, but since it's not there , the RPM's climb up and then start to drop down as the realization is made that there is no load ......Although for some reason i don't think that putting an automatic in Nuetral is such a good idea while the car is in motion....
 

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Discussion Starter #5
Stupid thing slips out of OD. If it keeps doing it too bad throwing it in neutral and back to D helps.
 

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have you tried replacing the MLPS sensor? they are about $90 from ford, but only $30 from napa . Almost all problems of slipping into neutral in the 1994 year of 4r70w's in our thunderbirds are caused by a bad MLPS (i.e. neutral safety switch) due to the fact that the 1994's did not have a gasket, so they were prone to corrosion. The newer one's have a revised gasket installed....

Courtesy of mn12performance.com
<img src="http://members.tccoa.com/94birdnj/mlps.jpg">
 
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