Okay picked up this 90 ef hatch. It's dpfi on the way home dropped 4 valves and piston rings were shot. But before this happened i noticed it had a high idle. Well long story short replaced head new piston rings rod bolts and bearings. After which i turned the idle down and then the Honda idle started.
I have cleaned the idle air control valve
Bled the coolant system
And alot of more
I have been working on hondas for years and never had this much problems fixing honda idle.

 

What do you mean by a Honda idle? The fluctuating or bouncing idle? Do you have any CEL? There is potential that the ports are plugged up on the manifold. Do you have a spare one to try?

I guess my main question is - What exactly is your idle doing? Is it slow, fast, not holding steady?

 

Honda idle? I'm assuming it's not staying steady and hoping around. Check you vacumn lines and replace the iacv if anything. Cleaning it doesn't always help.

 

Okay around here we call it Honda idle it's bouncing up and down but not a high one just up.....down.......up.......down. But i will try i have extra manifold and ill get a iacv

 

as stated above check for Vacuum leaks and then proceed to Replacing or trying another IACV.

Also have you cleaned out the Throttle body/intake manifold? or replaced the PCV valve recently?

Best of luck,Matt.

 

Okay i tryed everything new manifold,Iacv,pcv and checked for vacum leaks i even went ahead and replaced all the vacum lines. Also i cleaned the throttle body and intake manifold on the newer one and old one.

 

One more thing it is throwing a code. It blicks once......blicks again.......then fast 6 blicks

 

There is no code 26... Unless it is code 1 and code 16?

https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/mini-me-code-26-help-please-2630437/

Code 1 - O2 Sensor
Code 16 - Fuel Injector System

Troubleshoot code 16 = http://www.justanswer.com/uploads/hy...ic_code_16.pdf

ECU Code List = http://ef-honda.com/ben/ECUcodes.php

 

Okay thanks I will try that. But the thing is I still have a idle problem. If my iacv was bad it should throw a code but I know sometimes they don't throw a code. But let me ask this question I been working on b series for so long I forgot what to look at. But between my throttle body and intake manifold there seems to be a inch or half inch throttle body spacer idk if it is stock or not.

 

A spacer? No, there is a black gasket that is kind of thick though; it's no 1"...



(The yellow circle is the IACV.) Look at the black gasket under the throttle body - is that what you are talking about?

 

Yeah i know thats the iacv,But my gasket looks like that in a way ill try to post a picture here in a few. Im just already tired of d series now i know why i stopped messing with them lol

 

Okay as I stated once......I have since replaced the iacv valve twice along with the intake manifold..........Anyone have any other ideas why my idle is bouncing up and down?

 

As I stated before, if you have the codes you need to fix them first. DPFI is very temperamental to change.

 

Bingo!! That's the reason codes are thrown. To help you diagnos the problem. We can only do so much without seeing the car. Clear your codes well fix the parts causing the codes and go from there