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Weird Idle Problem!!

Old Feb 21, 2008 | 02:02 AM
  #1  
plethoric33's Avatar
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Default Weird Idle Problem!!

Tonight on my way home, my engine would start to kind of breathe heavy it sounded like when I would just be coasting. The idle would pulse about 5 or 6 times then return to normal. It didnt do it at first, just when it got warmed up. My temp wasnt high or anything. Any help on this one? Would the Idle valve going bad cause this? I put some fuel injector cleaner in hoping it might be that easy.
 
Old Feb 21, 2008 | 04:51 AM
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Default RE: Weird Idle Problem!!

Is the CEL ON?

Try cleaning the IACV and also bleeding the coolant system of possible air bubbles.

IACV cleaning:
http://www.superhonda.com/forum/f94/...r-iacv-144463/

Bleeding:
 
Old Feb 21, 2008 | 08:28 AM
  #3  
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Default RE: Weird Idle Problem!!

Well if it is the IACV then you need to clean it. Maybe its clogged up. Its located next to the throttle body and its a little black thing.
 
Old Feb 21, 2008 | 11:15 AM
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Default RE: Weird Idle Problem!!

How do you clean the IACV? Never had a problem like this so Im new to all this. The link up there didnt work for me. Just a blank page. Could you just take it off and soak it in some parts cleaner?
 
Old Feb 21, 2008 | 11:21 AM
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Default RE: Weird Idle Problem!!

Do all this with the engine off. Unbolt the IACV from the throttle body. It's metal, about 4 inches long, and generally round with an electrical plug on the end (The end with the plug is plastic). You probably won't have to undo the water hoses. Note that there are two holes in the surface that meets the throttle body, those are the air passages. There will undoubtably be some black gunk in them. Spray carb cleaner into the passages, let it soak, drain out, spray more in. After cleaning, make sure the gasket is still in place and bolt it back on.
 
Old Feb 22, 2008 | 06:54 PM
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Default RE: Weird Idle Problem!!

So today I cleaned my IACV and it didnt do a thing. It wasnt too dirty to begin with once I got it off. Still pulsates about 4 or 5 times after I come to a stop or throw it in neutral. So I guess Ill try bleeding my coolant system this weekend.

If its not the coolant system are there any other things it could be? Does the IACV ever go bad to where I might need a new one? Im thinking about getting some Sea Foam and running that in the gastank, crankcase, and fuel regulator too.
 
Old Feb 22, 2008 | 07:09 PM
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Default RE: Weird Idle Problem!!

If the CEL isn't ON and bleeding the cooling system doesn't help, then you may want to check for an intake air or vacuum leak.
 
Old Feb 23, 2008 | 02:15 AM
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Default RE: Weird Idle Problem!!

How do you check for an intake or vacuum leak? What can cause it and how do you fix it?
 
Old Feb 23, 2008 | 05:03 AM
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Default RE: Weird Idle Problem!!

Most common vacuum leaks are these:

cracked vacuum hoses
vacuum hoses disconnected or in the wrong spot
intake manifold gasket failure/leak
PCV valve stuck open
throttle body mounting gasket

there is a few more but i am tired and my brain hurts, but it's an excelent start
to check for a vacuum leak, the old school way of doing it is to spray the vacuum hoses and suspect areas with a carb cleaner or starting fluid. if you spray into the vacuum leak the engine will rev higher, because the fluid is sucked in through and burned in the engine.
 
Old Feb 23, 2008 | 06:22 AM
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Default RE: Weird Idle Problem!!

ORIGINAL: koots
to check for a vacuum leak, the old school way of doing it is to spray the vacuum hoses and suspect areas with a carb cleaner or starting fluid. if you spray into the vacuum leak the engine will rev higher, because the fluid is sucked in through and burned in the engine.
+1

In addition, if there is a leak, I have read that spraying carburetor cleaner may cause the engine to bog.
 

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