Dad's got a Y reg 2001 1.0 Micra.
When he got it, it could barely move under its own steam, unplugging the air mass meter made it run but stall, so i got a new air flow meter and that solved the running problem, apart from the idling.
Basically it revs itself on idle, and the revs also can stick at approx 3000 revs for circa 10 seconds before dropping low and then back to continuosly revving itself, sounds like between 800-2000 revs.
From cold it idles high, then once warm does the revving thing.
Now acommon problem with the older Micras are the curcuit board on the throttle body drying up and stripping it down and re-soldering the joints solve it, but this is the later Micra and does not have that early style throttle body, but a later Bosch one.
So far the following has been replaced:
Both lambda probes
Air mass meter
Coolant temperature sensor
I have also swapped a known working idle control valve onto it,and a used complete throttle body unit and it made no difference.
No fault codes come up when scanned.
Here is the interesting bit.
If you unplug the air mass meter it idles right for a few seconds then slowly increases the revs.
I also removed the throttle position sensor last night, turned it manually with a screw driver it did nothing at all to the way it ran :S
Also i put it on the emissions tester at work, and when its revving on idle its over fueling like crazy, AFR is twice what it should be, lambda is twice what it should be, but when held at circa 3500-4000 revs all leadings are spot on :S Then drop it back to idle and all the readings shoot back up to badly over fueling!
Im starting to run out of ideas, can anyone help?
Much love x
When he got it, it could barely move under its own steam, unplugging the air mass meter made it run but stall, so i got a new air flow meter and that solved the running problem, apart from the idling.
Basically it revs itself on idle, and the revs also can stick at approx 3000 revs for circa 10 seconds before dropping low and then back to continuosly revving itself, sounds like between 800-2000 revs.
From cold it idles high, then once warm does the revving thing.
Now acommon problem with the older Micras are the curcuit board on the throttle body drying up and stripping it down and re-soldering the joints solve it, but this is the later Micra and does not have that early style throttle body, but a later Bosch one.
So far the following has been replaced:
Both lambda probes
Air mass meter
Coolant temperature sensor
I have also swapped a known working idle control valve onto it,and a used complete throttle body unit and it made no difference.
No fault codes come up when scanned.
Here is the interesting bit.
If you unplug the air mass meter it idles right for a few seconds then slowly increases the revs.
I also removed the throttle position sensor last night, turned it manually with a screw driver it did nothing at all to the way it ran :S
Also i put it on the emissions tester at work, and when its revving on idle its over fueling like crazy, AFR is twice what it should be, lambda is twice what it should be, but when held at circa 3500-4000 revs all leadings are spot on :S Then drop it back to idle and all the readings shoot back up to badly over fueling!
Im starting to run out of ideas, can anyone help?
Much love x
