99 si with stock b16a2 (i/h/cat/e)

i tried to tweak my **** but i think i ended up makin it worse

i had a weak idle which stayed around 5-600 rpm. was also throwing random cylinder misfires (71-74) sometimes its 1 and 4, sometimes just 3, sometimes just 2, sometimes all of them, sometimes just 4... it sucked.

So I advanced my ignition timing a bit and those codes went away. I also adjusted the throttle body screw and tightened the throttle cable. It idled fine around 900-1k rpm.

Now sometimes the idle jumps from 1100 to 1500, to 1100 to 1500 and then sometimes stays at around 900 rpm. So sometimes it idles fine, then it starts bouncing up and down. I think i messed everything up when i was playing the the tb screw...

Now im throwing code 45(too rich/lean) and my fpr is sitting at 44psi(too high?) Same thing happens at 40 psi.

My CEL stays on and i got a shitty idle. Anyone know whats wrong?

 

More then likely you messed up your o2 sensor putting the header or cat on your car.....might wanna check/replace that before you do anything real expensive.

 

the standart idle is around 730rpm for b16a2 engines when it reaches maximum heat...
but in hot weathers when you drive your car and maybe stop on traffic light the idle stays at 1100rpm for some time then falls... thats normal i say...
but your problem is maybe cleaning the idle setter... my car had a same problem like that and i cleaned the idle setter... near the throttle somewhere there... take it out and clean it set your idle manually...
secondarily its maybe your o2 sensor...
if nothing works out fine i dont know then what it maybe

 

Without the aid of the IACV, engine speed should be around 500 rpm which is referred to as your base idle speed. When you plug the IACV back in, the idle should raise to what is called the curb idle speed (around 750 rpm).

If your base idle speed is set too high (which it sounds like it is), your IACV can not do its job correctly. The IACV can only add air to the manifold on top of what is being bypassed around the idle air adjustment screw.....so if the the bypass screw is letting too much air in, the IACV can't take it away.

Hopefully you did NOT mess with the throttle plate stop screw....did you?

 

the big screw with a flat head on the throttle body?... yea

 

ttt holy **** i have the same problem as you do i would like to know as well. what is weird is that...i dont have a cel at all?

 

ttt

 

3rweasdzasd

 

when u adjusted the idle screw did u unplug the iac u cant adjust the idle screw with out unpluggin the iac