cylinder cut out for warm up

[RSchlosser]

can anyone tell me if you can program the computer to cut 3 cylinders when warming up for winter operation. some say it,s automatic at cold temps.

 

[RonWeiss]

Nope you can't change it, the new 03/04's rely on an automatic high idle (1,000 rpm) to help warm them up.



I forget the conditions needed, below 30 F, idle for more than 2 minutes, parking brake on and not in gear... those are some of criteria the high idle requires to be made.



Ron W.

 

[Dean Upson]

The parking brake doesn't have to be on with the manual transmission (at least mine).



Dean-

 

[RonWeiss]

I could be mistaken, will try it out this morning before work.



Ron W.

 

[n9oig]

Does anyone have a truck that idles up to 1000 rpm immediately after releasing the key if its below 30 deg? Dealer tells me thats normal but I think that its dangerous the truck will do 20 mph in 3rd gear at 1000 RPM it wont idle down till it warms up.

I don't think out gen 3 trucks do the 3 cyl cutout just the 1000 rpm.



Kevin

 

[Dean Upson]

It is normal (at least for mine) for it to go right to 1000 rpm. It will idle down as soon as you hit the brake, and I think, the clutch as well. At any rate, it will not be idling at 1000 rpm when you take off.



Dean

 

[DFrank]

So is it bad to just start it cold and walk away for a few minutes? should I hit the brake to make it stop? if you make it stop, does it kick back in if it feels the need?



I reach in start the truck, then go inside for a few minutes to let it idle. I used to let it go much longer until i read some recent posts on the subject.



I have my keyless entry thing on a clip, so i can lock the truck while its warming up.

 

[n9oig]

Well Id agree with you but it does not idle down when you apply the brake or drive it. It will do 20mph in 4th gear at 1000 RPM, after it Idles for 2 min it wil idle back down if I step on the brake or move the truck.



Kevin

 

[DPelletier]

Kevin

Mine does that too. Will jump immediately to 1000RPM and stay there even if you do start to move (brake, clutch etc. ), despite the literature stating otherwise. I don't think its a problem, per se, and it does go away at some point, although I don't know exactly what tells it to (so to speak).



Dave

 

[Dean Upson]

I just went out and started my truck, it had not been run in 24 hours and it was zero last night and +16* when I started it. It went right to 1000 rpm and did NOT idle down to 750 rpm when either the brake or the clutch was applied. I misspoke earlier.

The truck will idle down only when the intake air sensor tells the engine it is warm enough to drop the rpm to 750. When the truck has been idling and warmed up and it ramps up to 1000 rpm, then if you use either the brake or the clutch the rpm will drop to 750.





Dean

 

[KBennett]

I started mine at 7* this morning and it went right to 1000 RPM.

I let it run for about two minutes while I cleaned the windows and when I got in, released the parking brake, and pressed the brake pedal it idled right down. I always let the truck warm up at least 30 seconds before driving off.

The visor says to let the truck idle for at least 30 seconds before driving, longer in sub-zero temps.



I have never had a problem with the high idle staying on.

 

[Dean Upson]

Originally posted by KBennett

I started mine at 7* this morning and it went right to 1000 RPM.

I let it run for about two minutes while I cleaned the windows and when I got in, released the parking brake, and pressed the brake pedal it idled right down. I always let the truck warm up at least 30 seconds before driving off.

The visor says to let the truck idle for at least 30 seconds before driving, longer in sub-zero temps.



I have never had a problem with the high idle staying on.

This had always been my experience as well. After reading this post and replying that my truck did idle down, I went out started it cold and did not let it warm up before applying the brake, etc and the truck did not idle down. If you let the truck warm up a bit the air temp will satisfy the gods in the sensor and let the truck idle down. I misspoke earlier because I have always let my truck run for a couple of minutes to warm up, this was the only time that I tried it stone cold and the truck acted as described in very first post on this thread.



Dean