Driver Activated Fast Idle

[HBarlow]

I recently learned something new about my truck. It has led a pampered life spending 99% of its nights securely parked in my insulated steel building out back.

About ten days ago I hooked up and pulled the fifthwheel out of the barn and parked on the front driveway next to the house overnight because we were leaving on a short RV vacation that morning.

When I went out to start the truck the temp was in the mid-20s and a coating of ice covered the windshield. I started the truck and let it slow idle for a minute or two then activated the fast idle with the cruise buttons.

I bumped the engine speed up in 100 rpm increments watching the EGT gauge for results. At 1400 rpm the exhaust brake was still closed and the pyro was indicating upward of 450*. I bumped the ACCEL button one more time and when the tach moved to 1500 rpm the exhaust brake opened and the pyro temp dropped. Obviously fast warm-up terminated.

It took me only four years and 111k miles to learn this. I had used the fast idle a thousand times. I use it routinely in hot weather if leaving the a/c running with my dogs inside and have used it many times in cold weather for warm-up or to keep the engine warm but I guess I had never bumped the fast idle all the way to 1500 rpm.

At a fast idle of 1400 rpm the engine quickly warmed enough to clear the windshield and warm the cab. I was silently thanking Cummins engineers for programming the engine to use fast idle and the VGT to quickly warm a cold engine and cold truck.

I realize some of you are thinking "mid-20s!" "That's a summer day up north. "

I know. I remember full well what winter temps were like when I was transporting.

 

[mwilson]

Ok Harvey,

Now when I get home tonight I have to try the '06 and see if that kicks everything out at 1500 or not. I can't remember and am now going to think about it all day... ... ... .



I usually set mine for 1200 rpm, engine brake on.



An interesting thing about that is the programming is smart enough to kick the brake off when the water temp is 170 degrees. If the automatic high idle has control rather than setting the cruise then that will drop the truck back to idle at 170 degrees as well. When the water temperature drops again (and it will at idle in cold weather) the brake will come back on and the idle will increase again.



It will set there for hours doing that to keep the water temperature up in the motor.



Bystanders will stare at it wondering what the hell it is doing, I have left it locked and running so "Buddy the Wonder Dog" doesn't get cold in a parking lot and when I come out of the store there will be a truck freak or two gathered around staring at it in sheer wonderment... ... ... ...



These are not low profile vehicles so if you are shy and don't like extra attention get a Ford... ...



Mike.

 

[HBarlow]

Mike,

The Sick. Ohh Furds get lots of attention also. Back when they were hot sellers when I was transporting I used to see one on a roll back wrecker or alongside the interstates stranded every day or two.

 

[RonD]

I recently learned something new about my truck. It has led a pampered life spending 99% of its nights securely parked in my insulated steel building out back.



About ten days ago I hooked up and pulled the fifthwheel out of the barn and parked on the front driveway next to the house overnight because we were leaving on a short RV vacation that morning.



When I went out to start the truck the temp was in the mid-20s and a coating of ice covered the windshield. I started the truck and let it slow idle for a minute or two then activated the fast idle with the cruise buttons.



I bumped the engine speed up in 100 rpm increments watching the EGT gauge for results. At 1400 rpm the exhaust brake was still closed and the pyro was indicating upward of 450*. I bumped the ACCEL button one more time and when the tach moved to 1500 rpm the exhaust brake opened and the pyro temp dropped. Obviously fast warm-up terminated.



It took me only four years and 111k miles to learn this. I had used the fast idle a thousand times. I use it routinely in hot weather if leaving the a/c running with my dogs inside and have used it many times in cold weather for warm-up or to keep the engine warm but I guess I had never bumped the fast idle all the way to 1500 rpm.



At a fast idle of 1400 rpm the engine quickly warmed enough to clear the windshield and warm the cab. I was silently thanking Cummins engineers for programming the engine to use fast idle and the VGT to quickly warm a cold engine and cold truck.



I realize some of you are thinking "mid-20s!" "That's a summer day up north. "



I know. I remember full well what winter temps were like when I was transporting.

Harvey, I hope you had all the water gone from the 5th wheel, they can have there own issues at 20 something over night, don't ask me how I know this, but I learned it the hard way 2 years ago.

 

[HBarlow]

Harvey, I hope you had all the water gone from the 5th wheel, they can have there own issues at 20 something over night, don't ask me how I know this, but I learned it the hard way 2 years ago.

Yeah, it was completely dry. RV trailers can be used, even lived in at very low temps, but preparation is required.

 

[Cosmo]

Mike,



The Sick. Ohh Furds get lots of attention also. Back when they were hot sellers when I was transporting I used to see one on a roll back wrecker or alongside the interstates stranded every day or two.

I remember pulling into FL, a 6. 0 blew past me at about 80 hauling a loaded 3-car hauler, then about ten minutes down the road he was sitting on the side in a big cloud of steam.



You couldn't give me a 6. 0, and if you did, it would get swapped out right quick.

 

[Simplysmn]

Mike,



The Sick. Ohh Furds get lots of attention also. Back when they were hot sellers when I was transporting I used to see one on a roll back wrecker or alongside the interstates stranded every day or two.

Harvey you see that Daily in Calif and multiple times on the weekend's :-laf:-laf:-laf:-laf

 

[EricBu12]

Harvey. I had the high idle enabled on my truck as well. . it was 14 deg the other day and i started the truck and put a pulp thermometer in the dash opening. . raised the idle and set it at the optimum rev with the turbo whining. . barely hear it. . anyway, in about 2 min, the dash was reading 80 deg air coming out. . not bad. .

Hey if my keystone Raptor 36' toyhauler, which has a ducted furnace in the floor, would it heat the tanks and water lines when in use in the winter? Some of my water lines are below the upper floor and next to the cargo storage door. . would that space be heated? or would I need to cut a small slit in the duct that goes to the bathroom and bedroom so that the cargo area would be heated?

 

[HBarlow]

Harvey. I had the high idle enabled on my truck as well. . it was 14 deg the other day and i started the truck and put a pulp thermometer in the dash opening. . raised the idle and set it at the optimum rev with the turbo whining. . barely hear it. . anyway, in about 2 min, the dash was reading 80 deg air coming out. . not bad. .

Hey if my keystone Raptor 36' toyhauler, which has a ducted furnace in the floor, would it heat the tanks and water lines when in use in the winter? Some of my water lines are below the upper floor and next to the cargo storage door. . would that space be heated? or would I need to cut a small slit in the duct that goes to the bathroom and bedroom so that the cargo area would be heated?

Eric,

All modern travel trailers are supposedly designed and built to put enough heat in the floor space where the water lines run to prevent freezing when the furnace is running. How well it actually performs can depend on several variables including the attitude of the crew installing the duct work and more.

I was able to remain quite comfortable in my old '95 Travel Supreme fifthwheel in northern Indiana winters when the overnight lows were 0* or lower by setting the furnace thermostat where the gas furnace would run some but using electric space heaters from Wal-Mart in the rear living room and front upper bedroom. Nothing ever froze but, of course, that old TS was a pretty expensive trailer when new and very well built. I bought it used and got several years of great service out of it before selling it. It is still in use as a full time home away from home residence for one of my son-in-law's job superintendents.

If some of the water line plumbing runs above the floor inside cabinets as it often does you can leave the cabinets open enough to circulate a little heat in very cold weather.

The water lines from water tank to pump are probably more vulnerable and may require additional insulation for low temps.

You don't mind working on things so you might consider removing some belly sheet metal near the water tank bottom and inspecting it. You could fiberglass house type rolled insulation, wrap around split foam tubing insulation, or a heat tape if needed. You can also cut an opening in the furnace to allow more warm air flow.

 

[AH64ID]

Harvey,

Does your C&C stop at 1,500 or go higher? The last C&C I used the manual fast idle on went up to 2,400 IIRC.

On my 05 the EB kicks off above 1,100 rpms with the ECM #22 pin grounded, it's supposed to be good to 1,350 with the clutch switch kit.

Personally I wouldn't go much above 1,100 with the EB on, that's a lot of fuel and backpressure on cold rings and you will increase the soot loading of your oil quite fast!

 

[WBlackburn]

Ok guys I have a new 2011. does it have the fast idle on it and how does it work????

 

[Simplysmn]

Set cruise control and then to adjust idle hit the accelerateagain to raise it the min you hit brake it will Idle down

 

[WBlackburn]

Schezzzzzzzzzzz thanks. did not know this !!!1

 

[BoeingDiesel]

And I thought I was (somewhat) technically oriented?? I’ve always wondered if there was a way to increase idle RPM for faster warm-ups and keeping my border collie cool in the summer while I run into a store. In the past, I just let the truck run at idle with the AC blowing. Just another reason the TDR. Gracias HB… et al.

 

[HBarlow]

And I thought I was (somewhat) technically oriented?? I’ve always wondered if there was a way to increase idle RPM for faster warm-ups and keeping my border collie cool in the summer while I run into a store. In the past, I just let the truck run at idle with the AC blowing. Just another reason the TDR. Gracias HB… et al.

Sorry for bad news but you may already know this. The manual transmission version of '06 and newer will not work without a minor owner modification. The simple mod is also discussed here in TDR.

 

[AH64ID]

Sorry for bad news but you may already know this. The manual transmission version of '06 and newer will not work without a minor owner modification. The simple mod is also discussed here in TDR.

It's a similar mod for 04-07, and and a different one for 07. 5-09 manuals. Without an H&S BM or MM the 10+ manuals are SOL.