idle problem

[GUEST_JDM]

when the car starts from cold it almost stalls (the idle jumps up and down from 300 to 600 rpm) after about 20 seconds it returns to normal cold start.
once temp guage reads middle, the car idles massive lumpy cam style as i have NO cams this is not good!( jumps from 800 down to 600 almost stalls then back up to 800 then normal for 30 seconds maybe then back through the cycle) driving around and booting it there is no problem seems to be fine apart from the extreem richness lol
ive checked near everything ive replaced every vacum hose n line, checked for any leaks in my cooler pipes, replaced my oxy sensor which helped a small amount,
im looking at now the air flow meter now
if any one has had this before or could send me in the right direction that would be good, ive also put the car on a carman scanner to check for any sensor faults but everything came up fine
cheers jared

 

[Nicely]

Have you cleaned the AFM hot wire? Take it off and use brake/carb cleaner on it. CAS sensor might need checking too.

 

[GUEST_JDM]

yeh mate i took the air flow meter and sprayed it with contact cleaner and um.. whats a CAS sensor, where is it n how can i tell?
cheers

 

[Nicely]

EC-90 in the workshop manual. TPS could be the issue too (EC-141).

Might be worth getting a Consult diagnosis.

 

[GUEST_JDM]

yeh ive had to up the idle screw to stop the car from stalling but im pritty sure that it's working okay but i'll check that to i'll borrow another diagnostic scanner tomorrow and plug her in and see what happens so im guessing there isn't much chance it could be my air flow meter then?

 

[Amused_15]

And while you're at it clean your injectors and fuel filter as well. The CAS is the roundish plastic bit that sits on the right side of the rocker arm cover. (viewed from the front) As for the tps, just unscrew it slightly and move it about until you're happy with the engine sound.

Dont muck about too much with the IACV screw. If you're using a DTS tool, just see if its value is 20%. You've a much better bet of running her back okay by just resetting the idle and ignition timing to 15-17 deg at 800-900 rpm.

 

[GUEST_JDM]

Hey yeah found the CAS sensor haven't tried another diagnostic as of yet but i did try different air flow meter's and the idle become a heap stronger and didn't jump as much as before (but still the same problem just less agresive) ..... so i'm guessing i'm on the path of my air flow meter is ****ed and my cam angle sensor as well, the car does take a few revolutions to start when cold or hot doesn't matter not sure if that points towards the cam sensor at all?
cheers for everyones help so far jared

 

[TriniGT]

Was any work done on the car? Maybe the cam gear skipped a tooth. Also take off the cold start module and clean it thoroughly, they like to get dirty and stick. Also check TPS voltage and maybe try and reset your idle as well.

 

[GUEST_JDM]

um.. heaps of work has been done to the car just nothing that should make it run on idle like it is, TPS voltage is fine as i checked that and i can still not find any faults i have tried a different diagnostic the other day and still found there is no faults too! not sure what the cold start module looks like or where it is so some help there could be good! and dont think cam gear as the car runs throught the rev range fine which also makes me think that it cannot be a cam sensor maybe cheers for everyone help so far jared

 

[130r]

I have idel problem ever since i have the bov (vent out) installed. this has been hampering me for the past one year, even with the hks eids installed it still happen once a while.
until a friedn suggest to remove the iacv to clean. We remove it and dimanting the internal (valve and spring) and dip it into the diesel for a while follow by using a brush to clean out the gum. Air dried and reassembled, we re intall the valve and start the car, you will need to adjsut the screw int eh iacv to adjust the idel. one adjusted we go out for a sping and to my surprise the idel was fine and the edis is working perfectly. all sudden shift to neutral will have the rev needle stop at 1k rpm before decending to 850 rpm.
No more idel nightmare.

But do remember to take picture during dismantling the iacv, there are 2 seperate valve and spring do not mix them up.

 

[GUEST_JDM]

okay maybe on to something now what does anyone know about the automatic choke on the s15 as i am thinking this is constantly on? (maybe?) as my idle problem only arises after 2 or so mins from cold start, the idle to me sounds like its over fueling on idle and pritty much sounds like its back firing on idle lol could i be on the right path?
cheers jared