So i am at the end of the rope with my idle issue on my 89 hatch. The car will start if i give it gas and try to idle and will usually idle around 2000 rpms then ease its way down to about 1200 then spike back up. and sometimes it will just drop and stall out. once it gets to about 1000 rpm it feels like it wants to die and runs a little rough. it was a dpfi car but i converted to mpfi. it has a new headgasket and rebuilt head. it drives great and makes good power for a d16. so far ive tried the following
New head gasket and rebuilt head
New ecu
New idle air control valve
New dizzy
New intake air temp sensor
New coolant temp sensor
Bled cooling system
New plugs and wires
Checked for vacuum leaks and replaced intake manifold gasket
New skunk2 throttle body and intake.
i cannot get it to idle low enough without it dying and the idle is never steady. im at the end of the rope and desperate and made an account just to ask for some advice. some help or suggestions would be greatly appreciated and like i said, im new to the forum so be easy on me!

 

No Check Engine Light?
Did you use a swap harness of some kind or did you modify the DPFI harness?
Did you calibrate the TPS?
What fuel rail and pressure regulator are you using?

 

its a d16y7 fuel rail and regulator i had to use to mount on the skunk2 intake. also no check engine light. and tps has been calibrated but probably needs to be done again because i have even tried to adjust the throttle blade screw to get it to stay running. and i modified the original harness for the swap.

 

What size is your throttle body?
You might need a smaller one
Post a photo of your throttle cable, it needs to have slack

 

I purchased the skunk 2 alpha series thinking it would help with issue but still idles like crap. And I read online about the slack in throttle cable and it definitely has slack. It's not loose but not pulling the blade open at all and the throttle cable is a new honda oem cable

 

Have you checked the resistance on your EACV? Unplug the harness and check the resistance across the the two pins on the EACV (not on the harness). It should be 8-15 ohms.

 

is that the "idle air control valve"?

 

Yes, sorry, IACV and EACV or sometimes used interchangeably.

 

ok I will give that a shot when I get home after work. Thanks

 

Remove and clean the iacv
There is also a screw on top of the TB, screw it in all the way and see if it helps

 

Thank you for the reply but I have cleaned the original iacv and it didn't help so I bought a new one and still no luck. It seems to idle really steady tho when the iacv is unplugged but when it's unplugged and I apply the gas it'll act like it hits a rev limiter around 3-4000 rpms and just bounces the rpms unless I go full throttle then it'll get past the "rev limiter " behavior and go to redline quickly