Rough idle

Hi. I've got a 2002 facelift and when the engines warm the whole car vibrates on idle you can see the steering wheel vibrating. It idles at 640 rpm according to torque on my phone. Any ideas why??
 
Would pull a spark plug lead off .. one at a time.... use something insulated with rubber or you will get a shock ... see if there is NO difference as my first thought is you may have a duff spark plug / lead etc .... In other words its only firing on 3 cylinders ?
 
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Its coilpack. Maybe the plug gap is too big. If I blip the throttle the revs settle and idle is fine for 6 second then car starts vibrating again. Don't think its running on 3 cylinders no sound difference or lack of power
 
If you blip and it settles for a short time i dont think its sparks ... more likely to be air leak or Idle control valve dirty etc ..... might be the rubber o ring on that ..... mine had gone and was causing rough idle (not sure if you have the same as my 95 ..... but worth looking if you have ?)
Is your dizzy cap, rotor arm all clean and not furred up inside / cracked / ?

Not sure if these apply to your as its a later model than mine ...
Other things to check .. MAF connector all okay ?
idle rpm maybe a bit low
Throttle body "resoldered" ?
Timing set correctly ?

Do you have the choke "waxstat" on yours ... is this operating correctly ? (black smoke from exhaust means running to rich)
 
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If you take TB off will be easy to get the IAC off .... would definately give it a clean and replace the o ring....... B&Q do a pack of o rings for about 1.99 odd that fit fine ... little smear of oil so it seats properly...... its so cheap its worth crossing of the list imho
 
ive got this issue, but on a 1.0L facelift non coilpack. i regularly (every 3 months or so) take off my t/b and clean it with brake and parts cleaner and it helps a lot, but only for a week or so. think i'm just going to increase my idle speed little by little until it sits and idles smoothly.

also worth noting that i only clean my t/b so much because i dont run an air box or filter.
 
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Car air filters are generally around an F7 or higher efficiency which should remove most particulate down to 1- 3 micron particle size.
Running without an air filter is much like sand blasting the internals of the engine / pistons / valves .......... and it likely wont last long....... although i expect the piston crowns are well de-coked.
Without an air filter your looking at 30% of contaminents running out of the exhaust, 50% goes into the oil to party elsewhere and 20% is unnacounted for .... ie inbeds itself into the engine surfaces.
 
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Car air filters are generally around an F7 or higher efficiency which should remove most particulate down to 1- 3 micron particle size.
Running without an air filter is much like sand blasting the internals of the engine / pistons / valves .......... and it likely wont last long....... although i expect the piston crowns are well de-coked.
Without an air filter your looking at 30% of contaminents running out of the exhaust, 50% goes into the oil to party elsewhere and 20% is unnacounted for .... ie inbeds itself into the engine surfaces.

An outbreak of uncommon common sense rationally applied to air filter function! How it avoids airborne particles contaminating engine oil turning it into grinding paste sludge.
 
ive run this engine for 35,000 miles and put it through 2 MOTs like that, and my previous one was the same, which ran 50,000 miles and also went through 2 MOTs, without any emissions failures. Sadly my pistons are still fairly coked up, on the last check approx. 1000 miles ago. i have a good supply of good oil which i change every 5000 miles, as well as a flush and a new filter afterwards.

i do look after my baby! i know its probably not the best solution for an inlet system, but you can't deny its simplicity and i love the noise!
 
On my fourth Micra, a 1996 after 3 K10s, each did over 150, 000 miles with no problems only servicing consumables.

When they got rather too tired for my liking I sold them on in running order with long MOT’s, crystallising my optimum care free cheap as chips motoring experience.

That is to put petrol in the tank and myself in the front seat and just drive the thing. There are much more rewarding and interesting things to be doing then unnecessary work on old cars.
 
ive run this engine for 35,000 miles and put it through 2 MOTs like that, and my previous one was the same, which ran 50,000 miles and also went through 2 MOTs, without any emissions failures. Sadly my pistons are still fairly coked up, on the last check approx. 1000 miles ago. i have a good supply of good oil which i change every 5000 miles, as well as a flush and a new filter afterwards.

i do look after my baby! i know its probably not the best solution for an inlet system, but you can't deny its simplicity and i love the noise!

You likely live and drive in clean air areas ..... and that is not as obvious as it sounds .... I used to fit the filtration for Didcot Gas Turbine and that is a filthy horrible area .... lots of large particles ...... only place worse was Saudi due to the Turbines sucking in sand ......... and I agree re the sound .... sounds great i bet .... but if your unlucky to follow a sand truck you will f the lump......... So just use caution in the hot periods when the dust starts kicking up from the road as thats all getting sucked it .... good job we live in Blighty ... lol dusty days are few and far between....... Also the flush will help :)

Last thing to say .... If cars were okay driving without a filter, Car Manufacturers wouldnt design and fit them .... but rather would make more profit.............But if you are enjoying it and its not effecting the engine presently .... carry on ...... and the way the Micras rot .. theres likely a glut of K11 unbreakable lumps laying about ;)
 
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