2000 civic dx with stock d16y7

My cold idle was 1800 and warm was 800. I didn't like the high cold idle so I decided to clean my IACV. Cleaned everything good and also took off my TB and cleaned that out. There was a lot of black stuff but it wasn't too bad.

Anyways I put it back together and now my cold idle pulses from 1500 to 2000 and my warm idle pulses sometimes but mostly stays at 1500 or maybe 2000 sometimes.

So what did I mess up? Everything was put together correctly. And I checked that little tab in the IACV and it's not sitting 180 degrees off.

The only other thing I did was take the butterfly valve out to clean it good. But I put it back exactly the same way.

Drives fine but idles weird. Any ideas?

 

You introduced air into the system. Did you bleed it?

 

Oh and when I turn the engine off, it shuts down really rough. Not sure how else to explain it. Used to just shut off nicely and now it shakes the car and shuts down.

 

damn forgot to bleed it. I'll go do that right now

 

yeah that didn't do it. is there anything on the TB that controls the idle? except for the idle stop screw of course...

 

Did you replace or lose the gasket and/or rubber o-ring behind the IACV? That can create a vacuum leak and royally jack up your idle.

 

Nope made sure the gasket and the little o ring for that sensor was good. It's being really weird and random, has to be a leak.. I'll take it off again and see.

Also, I reused the TB gasket. Can that be my problem? I really doubt it

 

Unless that paper gasket somehow came out fully intact (which would be a minor miracle) it might just be the problem. Whenever you pull the TB, you're supposed to replace the gasket. It's like, $3.

 

same thing happen to my gsr. Cleaned the IACV and now the idle fluctuates between 1k-2k. What're you suppose to bleed? and how?

 

Yea, I'm wondering the same thing. How do you bleed it? I'm having the same problem... I replaced the throttle body base gasket... Maybe i need to replaced teh iacv gasket... hmm...

 

By bleed I'm guessing they mean the coolant. And yeah the gasket was loose and not even stuck to either side I wasn't planning on taking the TB off so I didn't buy a gasket. Can ill replace it tomorrow and see if that fixes it

 

Oh and to bleed you just start the engine cold with the heater on and radiator cap off. As it warms up and the thermostat opens, air bubbles trapped in the system should "bleed" out.. Coolant level might drop so watch it and add more as needed.

 

http://i639.photobucket.com/albums/u...cture_4661.jpg

 

I repaced the tb base one... Didn't work... Lemme know if it works

 

I bet it is a leak in your IACV gasket. Had the SAME exact problem. Try spraying carb cleaner onto the joint between the IACV and the TB while the engine is running. If the leak is there, the engine will race a bit. Spray enough and the engine will bog and die.

 

Yeah I replaced the tb gasket and took the IACV off to make sure the o-ring is there. Cleaned everything again and put it back together. Still idles high.

I shut the engine down and unplugged the IACV. The idle started to pulse super quick, like 2 or 3 times a second. Plugged it in while the engine is running and still pulsing. Shut it down and restarted right away, stopped pulsing.

But now the idle is at like 3k. Or and when I give it gas or take my foot off the gas suddenly, it jumps. Doesn't stall out or anything but just like bogs for a split second.

Should've just left it as it was and lived with a high cold idle lol

 

It's something with the IACV for sure. When it's plugged in the idle is at 3k now, when I unplug it, it drops to 1500 and pulses really fast. I'll try some The Right Stuff gasket maker instead of the oring tonight and then go get a new o ring tomorrow.

 

Did you adjust the throttle cable too tightly? There should be as much as 1/2" of slack in the cable.

After replacing the TB gasket, did you torque the nuts and bolts to spec?

When the engine is high idling or fluctuating, pull the air intake system off and use your finger to cover the hole inside the TB leading to the IACV. Does the idle speed drop and steady?

Any CEL codes?

 

There's slack in the cable, i didn't mess with it. The code says idle control malfunction or something like that I can't remember. The engine speed drops and it idles smoothly if I cover that hole.

I ran out of carb cleaner but I'll get some in the morning and spay to see if there's a leak somewhere

 

Code P0505? This^ can be caused by the idle speed being out of adjustment. Have you followed the service manual procedure for adjusting the idle speed of your engine (see FAQs sticky)? If so, the next steps would be to test the TPS and ECT sensor.

 

Yeah that's the code. No i didn't adjust it at all. In the past if I took off a good working TB and put it on, everything was fine. I figured if it was adjusted before, it will be after. I guess I was wrong. I'll start from scratch tomorrow

 

yesssssssssssssss...im having his problem also!!!!!!!

 

So mine ended up being that idle adjustment screw on the throttle body. I just had to screw it in a bit and it started idling perfectly. I don't know how it got un-adjusted but I'm just glad it fixed it.

My cold idle is still kinda high though. The same 1800 that it was before I cleaned that valve. Any idea on why that's happening and how I can fix it?

 

Adjust idle speed and bleed coolant

 

hey guys, sorry didn't reply sooner. I'm glad you figured out what problem you were having. i'ma try adjusting the screw on the throttle body... hopefully that does it too. if not i will try spraying the carb cleaner in between the iacv and tb... thanks a lot guys.