Ok I have a problem with my car jumping the idle from about 450-2000 RPM when decelerating. Could it be the map sensor doing this? seems kinda like a vaccum leak.

2009 Ford Mustang V6
Automatic transmission? Does it jump around or go up and progressively drop over and over again. Just asking could be a locked up torque converter sticking.
--------------------------------------------------
'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.
It's not the torque converter doing it. it does it even in I drive it in low 1 and low 2 on decel it will constantly bounce from 450-2000 until I stop the car then it idles fine.

2009 Ford Mustang V6
If you doing even 20 in low decelerating the tach shouldn't be reading anywhere near 450rpm. does it feel bad or just read that?
--------------------------------------------------
'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.
It drops down to it like it's goin down to idle but then jumps back up.

2009 Ford Mustang V6
If you feel it lessen on the engine braking then gain it again when the tach drops then your transmission needs work. If you don't feel a difference but the tach falls it's electrical.
--------------------------------------------------
'96 Cavalier Good ol' Pushrod 2.2
-24X,000 miles on factory build
-Some oil loss between changes, me thinks it be rings.
David Jones wrote:Automatic transmission? Does it jump around or go up and progressively drop over and over again. Just asking could be a locked up torque converter sticking.
I have an 2000 Auto and it's done that jumping when decelerating now and then. Is it normal? Is there a fix?
Ryan1