CS3 idle issues "constant idle fluctuation"

[Meg@tron]

I'm having idle issues with my CS3 lancer...when I accelerate and then leave the car to roll between 20-50 km/h im getting a stutter as the needle constantly fluctuates up and down "hunting" within this speed bracket. I also get this same "hunting" issue on and off when the car is on park and even when in drive whilst waiting by a traffic light.......I've recently changed the idle control valve sensor, coil pack wires, spark plugs, serviced the throttle body and the issue is still there...the engine is a 4G13 btw. Any ideas on what might be the issue here????

[madman2961]

i have this same issue i have not done anything but cleaned the Throttle body but after seeing your list i am thing that the Timing of the engine might be off.

[spirited721]

viewtopic.php?t=643003

[Meg@tron]

Ok...btw the timing belt was recently changed as there was an oil leak in which the oil was coming out from the top of the engine where the timing belt is. I was wondering if this cud be a brainbox problem, as it took me a couple of months to source and change the idle control valve sensor which helped with the idle dropping extremely low wen the air condition is on :/
Ohh and thanks "spirited721"....I posted it there for advice as well

[chosen1]

Check both the iacv and egr. They may simply need cleaning.

[Meg@tron]

iacv was cleaned...still no change. What is ment by "egr"?

[MISHI]

timing will not cause hunting as you are describing... surging is from air that is getting in from a source it should not be... So anything from a intake manifold gasket to a hose to a seal in the intake will cause this.

one very reliable way to test is when it is surging, take a little insecticide and lightly spray a mist on the areas that carry connections to the intake that may possibly leak... just a puff. if the engine idle changes for any reason, there is a potential leak there.

A common area is the BISS or basic idle screw. This is a little plastic screw that carries a small rubber seal on the top or side of the throttlebody. you may want to spray a little mist there too. It isn't the easiest thing to change as the screw itself doesn't just pop out of the chamber... it takes some delicate work to remove it.

But check all the intake points for air getting in and see.

[deivid]

i had a surging once when driving....put injector cleaner in it and problem was solved

[ganeshlalchan]

Did you do the servicing yourself?
If so, then you are sure it was serviced.
If not, you should go over some of the servicing especially the iacv cleaning.

Had same problem with mine. That was the culprit.

[nissan4life]

You looking at vacuum leak. Mishi said it best
This happened to me already and it was just the hose from engine to air intake wasnt secured properly.

Also check and clean you pcv valve. Clogged/non functional pcv will allow air back into the chamber causing engine to have weird idle,stall or have poor performance.
Check egr(exhaust gas re circulation) valve. This has been discussed many times on CS forum and a lot of ppl who go thru the process of cleaning just blank it off to avoid carbon build up back into the manifold.