K11 facelift idle problems

Hi everyone,
This is my first post since becoming a member but I’ve been a Micra owner for close to 13 years now and thought now is a good a time as any to join the forum and see if I can help any fellow owners out there.

I own a 2000 Micra K11 facelift and noticed that a few people are having a few problems with the idle on the Bosch type throttle body.
The best tip I can give before you start to change the sensors is to check that the accelerator cable is well lubricated and that the adjustment nut near the throttle body has some slack in it. If it is tight, the butterfly valve can’t fully close which results in over or under revving when at idle as the sensors try to compensate. Even a small adjustment can make a big difference.
 
INTERESTING...
I was about to post about the sensors on the throttle body, the 3 of them. I am curious if the other 2(NOT the MAF) would cause the car to 'miss' when running in traffic at a slow speed?
Not a huge deal but it is starting to annoy me and make me wonder what is causing it.
Have changed the MAF a while ago and it made a world of difference so, puzzled.
 
OP
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M
I’m not quite sure what you mean by ‘miss’ addamf16 but it is possible that the other two sensors could cause idle issues.
If you are confident in removing the throttle body from the car, removing the sensors from it and thoroughly cleaning everything with carburettor cleaner, I would highly recommend it.
The sensors don’t really fail as much as people make them out to and changing them can be expensive and unnecessary.
The idle air control actuator which is the bigger of the three sensors at the bottom of the TB can clog up with carbon deposits and affect the running and is well worth cleaning. This could be the same reason why the new MAF you fitted saw a big improvement over the old one.
 
Sorry, by 'miss', I mean a sudden lag, similar to an MAF issue but different....Like it's about to stall, usually rectified by changing gear or a little push on the accelerator.
I am about to pull the tb tomorrow and do that very thing......I have one I bought from Ebay a while ago, ie robbed the MAF from it so...
Right, makes sense re the idle air control. Mine is a MKII facelift, Y reg so, anything I need to be aware of re said cleaning of the idle air control? Dos and don'ts?
I will be looking online and going through the Haynes.....curious re people with way more experience.
Thanks for the response.
 
Re the other IAC Actuator, the two 'screws' holding it on, what tool would you use for that? I have tried my Allen wrenches but, not go the right one so, was patient today vs trying to use the wrong tool :)
 
OP
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That’s what I thought you meant but I wasn’t sure :).
If you have an old toothbrush or something similar then that would help with the cleaning, concentrate on inside the throttle body housing beneath the mesh and plastic filters and by the butterfly valve where it’s hard to get to when not off the car.
If you can get your hand in and clean the inlet manifold after taking the TB off, that is normally dirty and worth doing while it’s accessible. Obviously try not to leave any fibres or contamination in there when finished though and don’t spray carb cleaner in there.
Apart from that I would say to let the sensors and throttle body dry before refitting and as mentioned before with the throttle cable, leave some slack in the cable when reconnecting so you can hear the butterfly valve slam shut when you let go of the tension in the cable. This makes sure that the valve can fully shut completely.
It’s worth noting that if you have a k&n filter or similar, the oil that’s on the filter can affect the MAF and that may require more frequent cleaning.
 
Cool!
I have a smokers toothbrush waiting :)
I had a good look at the TB I bought from Ebay so that all makes perfect sense.
I will take pics and come back to this tomorrow.
Many thanks for the advice/input....greatly appreciated.
I have the TS25 for the MAF, don't have other tools for that IAC so, will get them, needed so....
 
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