help please!



I just got a new FD3S (oxymoron) and it has a APEXi Power FC/Commander unit. It has several other mods like injectors, fuel pump, street port, 2mm apex seals, etc etc etc.



My problem is that the car won't idle properly all the time. The thing idles fast normally, and then slows to about 1000. However, every few minutes the darn thing starts fluctuating between 900 - 1400 RPMs in about 1 second cycles. Its really annoying, especially with a loud booming exhaust.



I don't know if the Power FC/Commander can fix this, even though there are settings for rev/idle in the unit. Also, isn't there a set screw somewhere in the engine bay for this?



Any help on getting my FD3S running smoothly is greatly appreciated. Thanks!

 

I had a similar problem... Check the upper and lower intake gaskets...My lower gasket was leaking...

 

Yes, you likely have a vacuum leak. Mine would do the same rev range when the PCV valve hose came off, but it tdidn't come and go, it was always there if the hose was off.

 

I'm having that problem now. I had perfect idle before I went to love my battery(disconnected my battery completely) and now it idles crazy...but when I put the A/C on...it idles perfect again...

 

Yeah mine did same as yours JSpec, after the weather changed completely I was all good to go after a couple weeks.



wile_e_coyote----Thats a bummer man, I have you drove it yet? If not take it for a spin, run it kind of hard see where your at after the dust settles.



Things to look into since the problem is vague

Coolant--Leaking, or old



Idle------Check to see where it is on the PFC, and also where your accesories put the idle at, might be too close together. That will do it.



Throttle possition sensor--- WD40 work it in and out (every little bit helps)



Battery-ALT---see what the ALT is putting out. See what happens to your idle if you use the A/C radio etc....



Hope that helps ya, its all FREE so start there..

 

i had the same problem, and i know how annoying it is!



take some wd40 and spray around to see if it is even a vacuum leak if you can issolate a specific area where the vac leak is it will be a lot easier to find. your car will idle really high if you get the wd40 anywhere near the leak. then check all surrounding vac lines. Helped me

 

First see if the idle smoothes out when you turn on the AC or the lights. If it does you have to dick around with the F/C A.E values in the idle settings. These #'s should be 200-300 higher than the idle settings. If the idle surges all the time no mater the elecrical load, AND you have driven the car around for a couple of days(sometimes it takes a while), try adding about 3% (ex. 1.21-->1.24) in the lower vacuum and lower rpm block. you find this by putting your commander on map trace function and seeing what blocks you are going through at idle. It should be the block that is lowest and farthest to the left. That would be the lowest vaccuum and lowest rpm you are hitting while surging. If the car idles, smooth after this, but is to rich, take fuel away from all the blocks around the idle block.

 

Hmm. That may be my problem then IGY. I'll give it a shot.

 

I am really glad you asked this question coyote. I am sure that I am having the same damn problem but I have been having trouble getting feedback. I think it has something to do with a poor thread description. I was idling too fast and then my problem morphed into the one you are having.



https://www.nopistons.com/forums/ind...howtopic=28749



If you could, would you please check this out and let me know if my problem description matches yours?

 

OMFG!!!! It worked! my idle is steady now! w00t!!!!!!!