1.0 auto niggle

[micra-se]

hello everyone my names karen and im new to this forum, iv been here before many times only to read though but now i need your help so typing is a must.lol
i have a 1.0 auto 2002 and upto last week was running great. the problem is with the auto box i think, when im driving at say 30mph at around 2000 revs for no reason the revs will jump upto say 3000 and i dont go any faster even though i have not moved my foot. other problem that may be related is the 5th gear seems reluctant to engage now. where as before it would fall into so to speak at an early speed it now seems to want to stay in lower gears more often than not. any advise will be passed onto my slave who i will make many cups of coffee for and have to put up with his moans and groans as he attemps to fix it..lol

 

[micra-se]

just to update. we have changed the oil in the gearbox and still have the same problem as before. if this fault was with a manual car it would be the clutch slipping. im now trying to find a pdf of the workshop manual somewhere if anyone could help with a link to a free download so we can check sensors.

also the haynes manual says there should be a switch on the accelerator pedal that sends a signal to the brain of the box as well as the throttle position sensor on the air mass body housing. but we have nothing on our model. im wondering if they changed this on our later model as our manual only goes upto a 1999. and ours is a 2002 k11. can someone who has a later manual please check if were correct.

 

[micra-se]

update number 2
well we have almost fixed this problem.
we changed the thermostate and the ecu sender above temp gauge. that at least lets us have all gears but i dont know if im just being silly but i think its taking to long to sense that the car is at peak temp. but at least it goes into top gear now.