Micra DIG-S rough idle / stalling

[SplanK]

Just to start a thread on this.

Our DIG-S Micra has occasionally stalled on me for no apparent reason in the past with the clutch fully disengaged such as waiting at junctions. It was always random, out of the blue and would me many months between stalls. I just put it down to bad luck/bad timing or something I did.

This morning there was 2 incidents. 1 at a junction where the idle went very rough and it was trying its best to avoid stalling. I went to fill up then drove home, 2nd time I was waiting at a set of lights, was idling happily for about 30 seconds then the rough idle came back then stalled.

It restarted and drive home fine. I could not get it to stall again although stamping on the break peddle does cause the idle to drop and I can hear the exhaust seemingly missing a beat. From the engine, I can here a 'pop pop pop....' type noise, its not loud but seems to correspond with the exhaust seemingly sounding odder than it was.

Not done any further diag work, but will check at lunch time and maybe get a diag reader on it to see what I can see!

 

[SplanK]

Just a quick update on this. The frequency of the stalling appeared to increase, including it happening to the wife (previously it only happened to me)

I mentioned the stalling issue to my mechanic when I took the car in for some suspension work. His advise was initially to check and clean the throttle body butterfly valve - its an easy enough task and inexpensive if I DIY.

So can of carb/throttle clean and a toothbrush I got to work. On initial glance the valve looked ok, however once I started cleaning a lot of grot came away. There is quite a bit of oil misting throughout the intake pipes - something that I wont be able to clean. The pipework isnt all that easy to remove but got there in the end.

The car was initially idling high, but wasn't sure if it was burning off excess cleaner in the intake manifold or in the process of doing a re-learn itself as it did come down.

I also used NDSiii android app to complete 'idle air volume learn'.

So far so good. The low idle/rough idle seems to have cleared up and the car has not stalled on us.

 

[SplanK]

Well its been almost a couple of months and many miles since I did this work and it still continues to be good and stalling or 'attempting to stall' has not returned.

 

[Celicasaur]

Thanks for sharing.

 

[SplanK]

Well, the idle stumble/stalling is back (well, has been for several months).

More often than not, the engine will stumble at idle and revs will drop quite low before it catches and regains its composure, but every now and then it won't catch it and it will simply stall out.

Unable to re-create either symptom on demand and no engine light. I do note the engine has a slight oil loss issue, but not significant (about half a liter every 4-5000 miles), nor have I worked out where the oil is going - there is never any spots on the ground, but when I last pulled the air intake there was a good coating of oil which is making me think oil is getting into the intake via the PCV system. There is no apparent blue smoke but I'm assuming at this point that the consumption is not significant enough to be visible.

Did my original cleaning do anything? I am doubting myself now and that I could have had a brief moment where all was ok. Maybe I need to pull it again and check over the condition. If there is an escape of oil through the PCV system and it consumes oil via the intake then the throttle body will gunk up quite quickly.

I did briefly consider is this an issue with one of the cam timing solenoids. On the note owners club, these solenoids seem to be a common thing to replace but I would assume the issue would exist throughout the rev range and bring up an engine light.

The procrastination on this continues!

 

[Spectre]

As someone who very recently experienced an almost panicky situation because of a failed injector coil on my K13, reading your car problem is making me anxious!

May be try decarbonizing the fuel injectors and the combustion chambers to see if it helps?

Some time last year I used Liqui Moly injector cleaner petrol additive on the K13 more than once and it smoothed out the drive for several days. I read that it clears the fuel lines too.

The effect was more pronounced on my Ford Figo 1.5 Tdci after using the Liqui Moly Diesel additive and going on a long drive; reduced turbo lag and better throttle response!

 

[SplanK]

Just to bring this to a close... We have 'solved' the problem by getting rid of the car! To be clear, we didn't get rid of the car because of this issue, but it was the right time for us to move on after ~11 years of ownership.

It has not stalled on us in a while, however, but we have noticed the idle was dropping and just about hanging on.
I did run an idle re-learn on it today which appeared to help, but not sure if that was down to sheer luck..... no idea what was causing the issue. My hunch is either a vacuum leak of some kind or maybe something squiffy with the PCV system.... it never ran poorly when driving, and doing a 40-mile round trip in it today, it didn't bat an eye lid with doing an indicated 80 (in Mexico of course!).

The idle re-learn was done via an Android app called NDSiii V 1.33 with the engine fully up to temp. We only have the car for a few more days so probably not long enough to determine if it does clear the issue, or for how long.

 

[Micra Paul]

After all of the Dig-s brain teasing entertainment foibles and frailties encountered, I am curious as to what will replace it & why for future less hassle motoring?

Needless to say I have enjoyed your many informative threads over the years .