Honda Prelude All Model Preludes

swap done everything works but idle bounces

Thread Tools
 
Search this Thread
 
Old Jun 27, 2006 | 10:53 PM
  #1  
preppy79's Avatar
Thread Starter
 
Joined: Jun 2006
Posts: 13
Likes: 0
From: Lehi, Utah, Utah
Default swap done everything works but idle bounces

well i want to say thanks to all of you that helped me on my swap problems and getting the vtec to work. car runs like a dream. but now my idle bounces when i'm stopped any ideas some say iacv and others say not enough amps
Reply
Old Jun 27, 2006 | 10:58 PM
  #2  
BB2_SI's Avatar
 
Joined: Mar 2006
Posts: 99
Likes: 0
From: Burbank, Ca, USA
Default

yah check all the Vac hoses. make sure they are connected right
Reply
Old Jun 27, 2006 | 11:15 PM
  #3  
preppy79's Avatar
Thread Starter
 
Joined: Jun 2006
Posts: 13
Likes: 0
From: Lehi, Utah, Utah
Default

kay thanks if you can think of anything else let me know pls
Reply
Old Jun 28, 2006 | 06:07 AM
  #4  
ItsSlowYo's Avatar
Honda-Tech Member
 
Joined: Jun 2005
Posts: 751
Likes: 0
Default

Just lean wit it...rock wit it.
Reply
Old Jun 28, 2006 | 10:10 AM
  #5  
MadCityLude
Guest
 
Posts: n/a
Default Re: swap done everything works but idle bounces (preppy79)

idle surge can also be caused from air in coolant
Reply
Old Jun 28, 2006 | 11:46 AM
  #6  
hella_usdm's Avatar
Junior Member
 
Joined: May 2006
Posts: 375
Likes: 0
Default

try screwing the idle screw in a tad bit and applying a little loc-tite to it. That solved my bouncing idle problem. If that won't work take apart the fitv under the throttle body and screw in the little white ring with two slots in it.

Search for "bouncing idle" and you'll find the pics.

heres some ripped info

High Idle speed and Fluctuation troubleshooting

Leaking EACV- Disconnect EACV connector. Idle speed should decrease. With the connector disconnected block the hole in the intake port or pinch the hose from the air cleaner to the EACV. If the idle speed decreases the valve is leaking. This condition will not set a code. The ECM can only detect an open or short circuit. It also may clog it’s screen if it has one.

Leaking IAC- (Idle air control valve) Disconnect IAC connector. Idle speed should decrease. With the connector disconnected, block the hole or pinch the hose to the IAC valve. If the idle speed decreases the valve is leaking. May not set a code and may not be a codeable circuit on all models.

TW or ECT sensor- (engine coolant temperature sensor) voltage should be about 3.0 volts @ 60 deg F and between .55 & .7 volts @ normal operating temp. If the voltage is above .8 volts at normal operating temp, will cause rich mixture and high idle speed. May not set a code because it is not far enough out of its operating parameters. **Also this sensor will not read temperature correctly if coolant is low. (beware)

Vacuum leaks- a loose vacuum hose or leaking intake manifold gasket can cause high idle speed and/or fluctuation. Also check for bad PCV valve.

Fast Idle Valve- (if equipped) a fast idle valve that is sticking can cause high idle speed and fluctuation. Check it by removing the steel cap on the top and putting your finger over the hole in the middle of the seat under the cap or block the port just inside of the throttle body opening, when the Idle is fluctuating or staying high. When the engine is warm this valve should be closed. You can tighten the seat but it will also change the idle speed warm up values (closing).

Throttle valve- throttle position sensor voltage should be .5 volts with the throttle closed. Make sure the throttle valve is fully closed and voltage is within spec.

ECU-If all else is good, if you reset the ECU and the problem goes away temporarily, the ECU may be defective.

The idle fluxes due to the fuel control programming built into the ECU, it notices that the engine is going too fast and that there is no VSS signal to the speedo, so the ECU cuts the fuel to the injectors to eliminate a higher than normal idle speed since the vehicle is not moving. Once the idle drops to a predetermined level the fuel injectors are turned back on and the vicious cycle starts all over again.

If there is air in the cooling system, it may be trapped at the engine coolant temperature sensor and the computer does not know what the coolant temp is but it knows that the engine bay is hotter now and that the O2 sensor is working so it goes bananas trying to keep things going, air may be trapped in the idle control valve, the one with two black small rubber hoses going in and out of it, there is also a screen in there that tends to get dirty and plugged, I have seen pics on H-T before of the parts break down but it didn’t show this screen with the rubber O-ring type gaskets, it is available with the O-ring kit here in Japan.


Reply
Old Jun 28, 2006 | 12:37 PM
  #7  
mmmtrbolude93's Avatar
Junior Member
 
Joined: Jun 2006
Posts: 251
Likes: 0
From: Beavercreek, OH
Default Re: (hella_usdm)

it really sounds like the iac valve... just go pick one up. it is an easy install. same thing went bad on my buddy's sol the other day
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
dc4b20
Honda Civic / Del Sol (1992 - 2000)
22
Dec 3, 2012 09:54 PM
jetlude
Forced Induction
5
Aug 1, 2006 11:09 AM
Excelerate
Honda Accord (1990 - 2002)
1
Jun 18, 2005 07:16 AM
killa_lude
Honda Prelude
11
Aug 16, 2003 08:33 AM




All times are GMT -8. The time now is 01:26 AM.