Automatic high idle

[Sully]

There is some talk on FSC about high idle. I have been talking to a tuner that I have dealt with for some time now. He can support the ODB II versions of our trucks, but doesn't market it all that much. I believe that he and I have found two options for a high idle mode. One is a switched application and the other is automatic. When the PCM senses the need, it would bump up the engine rpm to compensate.

There is a lot of why questions on the other site. Anyone who has had a buddy rev their engine while using a winch, knows how much easier this would make things. Some diesel trucks are equipped with a similar feature controlled from the cruise control. The option is used extensively by vehicles such as tow trucks to power the PTO for their winches.

This would come with a custom flash for your PCM to tune your afrs and such as well the commands to make the high idle possible. It is still in the testing phase, but I am curious if anyone would be interested in something like this. The idea is to run it in my truck under various conditions and see if we can find any bugs. Once the bugs are worked out, it would be available for sale.

 

[Sully]

This is about to go into testing on my rig. I am going to tie my truck to a tree and hook my winch to another to create enough load to bogg down the electrical system.

 

[IawoBill]

Idle Control

I have a 1990 with a rollback and would love to have a high idle. I was thinking of tapping into the system through the IAC with a stepper motor controller, but have not gone very far with it.

 

[silverado_06]

actually not a bad idea, i've thought about this on diesel's before and how useful it seems to be. let me know how this works out, i don't think i have any use fro it but i'm still curious.

 

[Butch]

Look forward to seeing the outcome. How hard would this be to run this to a switch?

 

[Sully]

well, the switch variation would be simple.... but the automatic variation is what we are currently working on. It would be only for the OBDII trucks for the time being. The auto version would by far be the easiest for the end user to install. Load a tune with supplied software or go to a local dealer for this tuning, and have them load it. Then enjoy. The switch would be loading a tune and then installing the switch.


I am being vague with who the tuning is being done through because I have him working on it as is, and he doesnt need more people bugging him. The way this tuning works is similar to a mail order, but you get real custom tuning (depending on vehicle) based off of logged parameters taken from your pcm. Its not like the pre written tunes that typically come in the mail. There are dealers for the tuning group which can be found on the website, and they have lower pricing than straight off the site. Either way, the owner does all the tuning himself.

I dont mean for this to be an advertisement by any means, and I left all the names out. This is meant more as a "how this would work" type of post. Once everything is done and tested, I will be sure to post where to find the info to purchase your tune with high idle. I am currently working on making my charging system as weak as I can for testing purposes. That means, pulling one battery and swapping the wifes smaller amp alt into my truck. Once my truck is ready, I'll end up using my 9500lb winch without a snatch block while my truck is chained to a tree. I want max load on the weakest possible charging system to provide a worst case scenerio. A similar type of work environment bogged the wifes 95 out and shut it down. She had to hold the rpms at 2500 to keep enough juice to lift my buddies jeep out of the revine. I doubt the average type of stuck will load that much, and most guys run smaller winches at less than 150" of cable without any snatch blocks. So that is a pretty extreme set up that I would only ever do if I absolutely needed to. The load it created on the charging system is exactly what I am looking to duplicate for the testing of this high idle system.

 

[Hogg]

GM used idle control in the LP4/L21 engined trucks. Since these trucks only came with the 80 pin x 2 connector 512kb PCM's, I doubt this will work on the blackbox trucks as the L21/LP4 trucks also run ETC.

Swap to a 896 or 411 PCM, swap over to CNP and ETC along with an L21/LP4 calibration and you can probabably run the stock idle control that uses teh cruise control switches to raise and lower the idle.

Here is teh stock info for idle control
http://www.gmupfitter.com/publicat/bull/bull24.pdf

peace
Hog