Go Back  Offshoreonly.com > Technical > General Q & A
IAC bouncing 0 to 1 at idle... >

IAC bouncing 0 to 1 at idle...

Notices

IAC bouncing 0 to 1 at idle...

Thread Tools
 
Old 09-15-2006, 04:11 PM
  #1  
Registered
Platinum Member
Thread Starter
 
Join Date: Jan 2001
Location: Houston, TX
Posts: 2,411
Likes: 0
Received 0 Likes on 0 Posts
Default IAC bouncing 0 to 1 at idle...

Had a board member over lastnight to give me a hand with the Whipple idle issues. I replaced the TP sensor and IAC motor on the motor.

We hooked the scan tool up and read the TP sensor , which read about .66 at idle. The IAC was bouncing between 0 and 1 count. The only time we saw the IAC motor counts go up was when we hit the throttle a little bit and it read between 20 and 32 counts, but that was just barely giving it throttle.

There were no error codes. Not sure what to make of it.

Anyone out there run into this problem before? Especially with a new IAC motor and TP sensor? Keep in mind there is maybe 2 hours on the new engine since i came off the dyno. When I put it in the water and try to shift it in gear, it dies everytime. If you goose the throttles once your shifting it in gear you might get lucky and keep it idling without dieing. It will however shift into gear with no problems on the hose, but thats becasue there is no load on the prop from what I can tell.

I wanted to thank Capt. Ross for taking the time to come to the house lastnight. I made sure the cocktails were there so he wouldn't have to rough it in the Texas heat!!

Now,,,maybe one day Dustin will email back and help me.
29scarab is offline  
Old 09-15-2006, 05:20 PM
  #2  
Registered
 
txriverrat2001's Avatar
 
Join Date: Jan 2004
Location: Channelview, Texas
Posts: 913
Likes: 0
Received 0 Likes on 0 Posts
Default Re: IAC bouncing 0 to 1 at idle...

Hey there!! I talked to Dustin a bit ago - he gave some insight on things to check before getting into the ECM and working the timing and IAC speed - so!

Maybe if it's not to crappy Sunday - and I get that damn IMCO stripped we can try a couple of things at the river??

I'd call ya but every time I get a second some other a$$ is in my office wanting something.

Dustins ideas - unplug the CTS to trick the brain into full rich (Cold) work the timing at idle and see if there is a sweet spot (16 vs 8) If the timing thing works - we'd have to work on the ECM. Do you still have the specs on the cam??? You mentioned over .600 lift? Or was that "Is this our 6th beer?" LOL!

Thanks for the cold beverages!!

Damn - Here comes another pain in my .....

LATER!~!!!!!!
txriverrat2001 is offline  
Old 09-15-2006, 07:23 PM
  #3  
Registered
Platinum Member
Thread Starter
 
Join Date: Jan 2001
Location: Houston, TX
Posts: 2,411
Likes: 0
Received 0 Likes on 0 Posts
Default Re: IAC bouncing 0 to 1 at idle...

I'm there bro!

I'll call ya sunday morning and see if we might be able to hook up. I'm going to have to meet you at a ramp. I'll be paranoid to back it off the trailer. I'm chicken when it comes to going into docks not knowing if it going to die on me!

And your welcome for the drinks! Thats was a good excuse for me to drink to!! I have someone else to blame it on!!
29scarab is offline  
Old 09-16-2006, 02:43 AM
  #4  
Registered
 
mats's Avatar
 
Join Date: Oct 2002
Location: Stockholm, Sweden
Posts: 379
Likes: 0
Received 0 Likes on 0 Posts
Default Re: IAC bouncing 0 to 1 at idle...

Maybe the throttleplates do not close completely, therefore the IAC does not go into operation until it is too late
mats is offline  
Old 09-16-2006, 07:36 AM
  #5  
Registered
Platinum Member
Thread Starter
 
Join Date: Jan 2001
Location: Houston, TX
Posts: 2,411
Likes: 0
Received 0 Likes on 0 Posts
Default Re: IAC bouncing 0 to 1 at idle...

Originally Posted by mats
Maybe the throttleplates do not close completely, therefore the IAC does not go into operation until it is too late
From wht we saw on the scanner the TP reading was .66. This would tell me the blades were completely closed. I did however take the throttle body off and makes sure the blades were sitting on the blade stops.

We still could not ge the engine to idle below 1000rpm.
29scarab is offline  
Old 09-16-2006, 10:50 AM
  #6  
Registered
 
mats's Avatar
 
Join Date: Oct 2002
Location: Stockholm, Sweden
Posts: 379
Likes: 0
Received 0 Likes on 0 Posts
Default Re: IAC bouncing 0 to 1 at idle...

The IAC count indicates that the air is entering somewhere else than trough the IAC. Some other vacuum leak?
mats is offline  
Old 09-16-2006, 11:00 AM
  #7  
Registered
 
txriverrat2001's Avatar
 
Join Date: Jan 2004
Location: Channelview, Texas
Posts: 913
Likes: 0
Received 0 Likes on 0 Posts
Default Re: IAC bouncing 0 to 1 at idle...

Dustin also thought there may be a possible air leak creating a lean condition - but with the size of cam - lack of manifold vaccuun - who knows. Whipple told me it was normal for one of these setups to run with a 0-5 count on the IAC. I'm betting vaccuum leak - but more investigation is needed.

BTW - Ya gotta love this quote - "OK-- Enough idle chit-chat. This ain't no fk'n retirement home..
Everyone!! Get back to your oars. The Captain wants to waterski."

Capt Ross

over and out!
txriverrat2001 is offline  
Old 09-16-2006, 12:12 PM
  #8  
Registered
Platinum Member
Thread Starter
 
Join Date: Jan 2001
Location: Houston, TX
Posts: 2,411
Likes: 0
Received 0 Likes on 0 Posts
Talking Re: IAC bouncing 0 to 1 at idle...

Originally Posted by txriverrat2001
Dustin also thought there may be a possible air leak creating a lean condition - but with the size of cam - lack of manifold vaccuun - who knows. Whipple told me it was normal for one of these setups to run with a 0-5 count on the IAC. I'm betting vaccuum leak - but more investigation is needed.

BTW - Ya gotta love this quote - "OK-- Enough idle chit-chat. This ain't no fk'n retirement home..
Everyone!! Get back to your oars. The Captain wants to waterski."

Capt Ross

over and out!
I bets that where the bleed by rock filter on the bottom side of the Whipple comes into play....yeah ...I know.....back to work!
29scarab is offline  
Old 09-16-2006, 07:24 PM
  #9  
Registered
 
Join Date: Oct 2000
Location: Spicewood, Texas USA
Posts: 1,382
Likes: 0
Received 3 Likes on 2 Posts
Default Re: IAC bouncing 0 to 1 at idle...

Sounds like there is some type of intake leak or the throttle blades not seating. If you don't have any luck fixing it yourself I can fix it for you, if towing it up to the Austin area is not too inconvienient for you. I am a Whipple dealer, can reprogram the ECM and have a prop shaft dyno. I can't do it for free, but I'll get it right and not rape you. Dustin is always covered up. It works a lot better if the customer works through a dealer(usually whoever sold you the SC). Part of their responsibility is to help you with issues like this...at least that's what I do for customers I sell to. I just sold a Whipple to a customer in Colorado and I've been on the phone about 10 times this week answering installation questions.
bobl is offline  
Old 09-17-2006, 07:29 AM
  #10  
OSO Moderator
Charter Member
 
BillR's Avatar
 
Join Date: Oct 2000
Location: Virginia Beach, VA
Posts: 3,580
Likes: 0
Received 3 Likes on 3 Posts
Default Re: IAC bouncing 0 to 1 at idle...

Check the timimg first. I had same problem and thought it was IAC / fuel related. Timing was advanced 11 degrees too much.
__________________
BillR

'00 Scarab Sport 302 CC
'02 Cigarette Top Gun TS
'02 PQ 340
'00 PQ 280
'98 Scarab 22
'97 Baja Outlaw 20
'72 Checkmate
'65 Glastron
BillR is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
MILD THUNDER
General Q & A
1
07-20-2005 12:19 AM
onesickpantera
General Boating Discussion
10
07-18-2005 02:21 PM
BlownBajaOnHavasu
General Q & A
3
07-13-2004 12:24 PM
Risk Taker
General Boating Discussion
12
02-06-2003 12:02 PM
Risk Taker
General Boating Discussion
6
11-25-2002 07:22 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



Quick Reply: IAC bouncing 0 to 1 at idle...


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.