if it drives normal except when you let off the gas the rpm jumps then it is a map sensor
If it's just the gauge jumping and there is no actual increase in RPM, then the gauge or the pickup is faulty. If the RPM is actually climbing as you drive, your transmission could be gearing down or your transmission is slipping under load, automatic or standard.
what is wrong with my rpm it goes up and down
In the sentence Jumping up and down is a bad idea if you have just eaten chili dogs., the phrase jumping up and downis the subject.
no.
Jumping up and down
do you mean warmed up ,at idle, the rpm surges up and down with out foot on gas ?
Rpm stands for revolutions per minute. This is talking about the revolutions the crankshaft goes per minute. The faster you go to more revoultions that are accomplished. Therefore the faster you go, the rpm goes up. And as you slow down it goes down.
Hopping
You come up, you come down.
jumping up and down
Of course because your Body Begins to warm up causing sweat after a while, and the thermal energy Comes from that movement where you are jumping up and down . (HOPE THIS HELPED)* !!:D
a force witch is called up and down and also gravity