I have T5 2.5 turbo Drive for about 5 minutesthen it starts to judder between 1500 to 1800 rpm gets worse on light throtle .put foot on throttle or back off and judder goes away then ASR light comes on .Juddering or missing doesnt get any worse. If you turn engine off and restart juddering gone for approx 5 minues then returns.Doesnt seem to blow black smoke only faulty code cam position sensor which has been replaced

FORGOT TO SCAN THE PCM I SEE.
check all fuses.?
not told
fails hot and cold engine or both
car must be in transmission DRIVE selected? right?
and foot off gas pedal (accelerator)_ rpm goes to 2000 or up to 6000 rpm . and or
so driving foot off the pedal and RPM goes too high
or in drive, I step on the throttle (gas) and RPM shoots way high
and Never leaves 1st gear. that is transmission failures.
in DRIVE.
if rpm also goes that high right foot doing nothing and in park
that is engine idle control's failing.
we can not see you drive or how. so answers can be a tad hard.
in what gear? PRNDL (choices)
right foot doing what?
and what SPEED is too slow 20 or 85mph? or?
does tranny fail to upshift?

tell what it does in drive. (selector)
how fast in drive,? MPH 5 ,10 ,20? what?
is the throttle pedal dead. RPM cannot be raised right foot in drive.?
or yuou race fast the engine, right foot but speed does not increase?
or speed does increase fast and RPM fast but transmission fails to go to 2nd gear.?
scan the car is step one,
is check engine lamp on ,? idle or moving

you might try cleaning the throttle body first. Buy some good Throttle body cleaner and a old tooth brush take off the air intake hose to the engine, have a friend hold the gas pedal to the floor with the engine off and spray and scrub the throttle body good replace the tube crank it up and rev it up a little to clear out the cleaner this may fix your problem

hi i would try replacing the throttle position sensor as these cause similar probs

check out your throtle position sencer

its very important that the throttle body especially around the throttle blade be spotless clean or they will stall every now and then. then progress to refuse to idle at all. take off the rubber air intake pipe from the top of throttle body [has 3 torqes screws] open throtle by hand and look for carbon/grease/soot etc were the throttle sits when closed. clean with toothbrush and some caeb cleaner get all black off and dont forget the blade, both sides and the edges. scrub then rinse with carb cleaner untill shiny.spray some cleaner in the hole that is on top off the body to. that is your idle air controll motor port.put back together.it will be hard to start at first so hold gas pedal half way down untill it starts then slowly [real slow] let foot off untill you are no longer pressing it. put in reverse and let it idle there a few seconds then do the same in drive. that should do it. sometimes it may stall a couple of times when driving dont hold foot on gas just let it die then restart this allows the computer to readjust its idle stratagee

if you have cruise ensure that isn't interfering with the throttle linkgae near the engine above the injector pump. could be injector pump giving you issues.

chances are this vehicle is what they call "drive by wire". it incorporates 2 position sensors, one on the accelerator pedal and one on the throttle body. if one is not working it will not accelerate. have it towed to your dealer to be corrected.

I researched this & you need to replace the throttle body gasket & get the throttle body re-calibrated. Seems to be dealer only. Also, the t.p.s. (throttle position sensor) could be bad.

I would start with the TPS, and if it doesn't solve it then the AFM would be the problem.