High Idle Mod A+
Elder User
Joined: Oct 2006
Posts: 624
Likes: 0
From: north texas
i dont mean to hijack , but i have done this same upfitter switch and high idle mod install on my 2006 f250, but i just had an egr delete kit installed , so do i still need to flip the high idle on with an egr delete installed? since i have no egr to clog any more do i need to still idle high rpms when in park?
Senior User
Joined: Sep 2006
Posts: 187
Likes: 0
From: northeast missouri
I got the latest reflash done when i had my ficm replaced and now my truck goes to a high idle after sitting for a few minutes it only does it when the temps are lower say around 35 to 40 and it only does it when the ECT is between ambient air temp and 170. surprised the hell out of me the first time it did it. but it idles up to about 1000 rpms shuts off after you step on the brake. e brake is not engaged.
Postmaster
Joined: Jul 2005
Posts: 3,956
Likes: 6
From: Abilene, Texas
I have done this on serveral trucks (5). It seems that some you have to press in the e-brake some you don't. Doesn't matter how it is hooked up. I'm not real sure what makes it one way or the other. If it goes by year, or flash, or what?
More Turbo
Joined: Mar 2010
Posts: 599
Likes: 85
From: Bakersfield
I got the latest reflash done when i had my ficm replaced and now my truck goes to a high idle after sitting for a few minutes it only does it when the temps are lower say around 35 to 40 and it only does it when the ECT is between ambient air temp and 170. surprised the hell out of me the first time it did it. but it idles up to about 1000 rpms shuts off after you step on the brake. e brake is not engaged.
With trucks that have a recent flash that sends RPMs to around 1k on cold mornings is the high idle mod necessary?
New User
Joined: Oct 2010
Posts: 13
Likes: 0
07 f350
can someone email me the instructions for 07 350 instalation ts02paul@gmail.com
i dont have the aux switches so also include what i need to do to add a small toggle switch under dash
thanks
i dont have the aux switches so also include what i need to do to add a small toggle switch under dash
thanks
Lead Driver
Joined: Oct 2010
Posts: 5,420
Likes: 16
From: Ouray, CO
Ok, that makes sense now.
While in NC last weekend, it was 30* in the morning
while packing up, I had the Ex running to warm up.
I noticed the idle kicked up to 1k also. I was stunned,
I thought something bad was going on.
(gee maybe the parking brake was on too?, not sure now)
*IF* it gets into the 30s this winter I'll pay more attention.
While in NC last weekend, it was 30* in the morning
while packing up, I had the Ex running to warm up.
I noticed the idle kicked up to 1k also. I was stunned,
I thought something bad was going on.
(gee maybe the parking brake was on too?, not sure now)
*IF* it gets into the 30s this winter I'll pay more attention.
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Tuned
Joined: Jan 2009
Posts: 269
Likes: 3
From: Newnan, GA
Is the mod neccessary...
Probably any time the truck idles for an extended period, the high idle would give you a higher alternator output, more coolant flow, better A/C and heat function.
While writing this response I just read a few threads about alternator output, voltage, and the effect of low voltage on the FICM. Seems like low voltage will eventually ruin the FICM, an expensive part. I can see that extended idling in summer heat, front and rear A/C fans running, might cause a low voltage condition? Maybe maybe not. To be on the safe side I am going to do the High Idle Mod this winter!
Tuned
Joined: Jul 2009
Posts: 489
Likes: 4
i dont mean to hijack , but i have done this same upfitter switch and high idle mod install on my 2006 f250, but i just had an egr delete kit installed , so do i still need to flip the high idle on with an egr delete installed? since i have no egr to clog any more do i need to still idle high rpms when in park?
However, from what i've read so far. It appears that this mod is good and should be used regardless if EGR has been blocked/deleted as the high idle keeps your truck's electrical system fully charged keeping all electrical components working properly.
Fleet Owner
Joined: Nov 2003
Posts: 27,924
Likes: 3,649
The strategy only keeps the idle up for a limited time IIRC. You really need the elevated idle for several reasons. Yes it helps your electrical system somewhat, but it also helps get your engine closer to operating temperature (which is hard to do w/ a diesel engine at idle).
Elder User
Joined: Oct 2006
Posts: 624
Likes: 0
From: north texas
i have done the high idle mod and upfitter switch install, it is a great mod to install, it is about 25 degrees where i am at right now, i just went out and flipped the high idle on (Aux-4 swicth) , so she will be nice and warm when i get in her in about 5 minutes, also in the summer it works great to keep a/c cold when at idle, i was also told it can prevent wet stacking in the engine by using high idle when setting still for long periods, when i flip my high idle switch i see the rpm's jump to about 1300rpm's, this mod works well when u are trying to jump a dead battery off also, this mod is worth every penny, in my opinion.
Freshman User
Joined: Oct 2010
Posts: 32
Likes: 0
From: Eagle River AK.
Just for info sake, on my 04 per the mod directions in the 6.0 tech folder (great resource) I direct wired wire 322 and wire 294, worked like a charm she went right up to 1200 rpm.
I was going to leave it as just a hard wire but this morning it was –5 degrees, and needless to say the truck was a bit chilly. I have an auto start on the rig so I sit in the house drinking coffee while I fire her up. She started fine and went right to high idle. She did sound a little rough at first but smoothed out in about a minute or so at high idle. After listening to her this morning in the cold I added the toggle switch, very easy.
I just feel I will let her warm up a bit with the auto start, then I’ll walk my lazy a$$ outside and flip the switch. Great mod, thanks to all who contributed to it. HOOAH
I was going to leave it as just a hard wire but this morning it was –5 degrees, and needless to say the truck was a bit chilly. I have an auto start on the rig so I sit in the house drinking coffee while I fire her up. She started fine and went right to high idle. She did sound a little rough at first but smoothed out in about a minute or so at high idle. After listening to her this morning in the cold I added the toggle switch, very easy.
I just feel I will let her warm up a bit with the auto start, then I’ll walk my lazy a$$ outside and flip the switch. Great mod, thanks to all who contributed to it. HOOAH