[Diy_efi] High idle after highway driving

[Bill Hamilton]

If this was a conversion then my question is:
Does it have a VSS?
While fine for off road, there are driveability issues with not running one.
I also run a little higher IAC count(about 40) at idle so it has more room to adjust idle should it get lost.
The IAC counts in the data log have nothing to do with the actual position of the IAC since there is no real feedback.
The counts are based on where the ECM thinks the IAC is.
AFAIK-that's why it does a reset at different times to ensure it knows the position.
One is while driving. the other is on shut down. The last thing it does is drive the IAC closed then it goes to the park count specified in the bin.
 
Stalling when coming to a stop is also a side affect of no VSS. 
 Bill
 
> From: aaron at creativeoverdrive.com
> To: diy_efi at diy-efi.org
> Date: Wed, 26 Jan 2011 08:37:28 -0500
> Subject: Re: [Diy_efi] High idle after highway driving
> 
> If it worked before and is only messing up recently, then a sticking IAC is
> a good possibility, like Mike says.
> A plugged passage is also a place to look.
> 
> Do you see the high count position during your in town driving?
> Since the GM TBI IAC is a stepper motor basically, it may have a bad
> position.
> 
> -----Original Message-----
> From: diy_efi-bounces at diy-efi.org [mailto:diy_efi-bounces at diy-efi.org] On
> Behalf Of Mike
> Sent: Wednesday, January 26, 2011 3:58 AM
> To: Ashley Wagner; Do It Yourself fuel injection
> Subject: Re: [Diy_efi] High idle after highway driving
> 
> By IAC I guess u mean Idle Air Adjust,
> 
> Can you tell if the unit is jamming due to high changes or anything else,
> perhaps less vibration at highway, round town its shaking more as engine
> revs up and down... Is the pwm signal to it different, does the O2 feedback
> loop stay on when idle on TPS, tried tapping the IAC to see if it shifts up
> or down
> esp after highway cycle etc etc,
> regards
> mike
> 
> At 02:47 AM 1/26/2011, Ashley Wagner wrote:
> >My 7747 does not want to idle down below 1000 rpm after I have taken 
> >it out on the Highway. The IAC stays out at a high count and does not 
> >readjust. It does not do this when I drive it around town, any 
> >suggestions???
> >_______________________________________________
> >Diy_efi mailing list
> >Diy_efi at diy-efi.org
> >http://lists.diy-efi.org/mailman/listinfo/diy_efi
> 
> _______________________________________________
> Diy_efi mailing list
> Diy_efi at diy-efi.org
> http://lists.diy-efi.org/mailman/listinfo/diy_efi
> 
> _______________________________________________
> Diy_efi mailing list
> Diy_efi at diy-efi.org
> http://lists.diy-efi.org/mailman/listinfo/diy_efi
 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.diy-efi.org/pipermail/diy_efi/attachments/20110126/43d8d159/attachment.html