Idle speed cold weather

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Feb 23, 2009 | 12:42 PM

hammer65

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From: Morehead, Ky.

Idle speed cold weather

I searched for this, but found nothing, so here goes.
In cold weather (20 deg.) I start my truck and the idle speed goes to 1000 rpm. This seems a little high, but OK. After about 10 minutes warm up, I tap the throttle and the idle goes back to 600 or so. This morning after this happened, I drove about three miles, left it idling, went in for coffee,(5 min) came back out to a 1000 idle speed. The temp gauge was about 1/4 up on the gauge. My question is, is this normal?? Thanks to all who respond. Hammer

Feb 23, 2009 | 12:43 PM

superduty4x4

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From: Newport, WA

Yep, normal. The high idle mode helps the engine warm up faster, and keeps the cylinders from washing down (aka wet stacking).

Feb 23, 2009 | 01:31 PM

Ponyboychris

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From: Kiowa CO

Like Chase said, normal operation for these trucks in cold weather and cold truck.

Feb 23, 2009 | 04:20 PM

hammer65

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From: Morehead, Ky.

Thanks guy's: I worked for a Caterpillar Dealership for 42 years and I never heard of Wet Stacking.I did look it up though. Contractors used to fire them up a 1/2 hour before shift started and shut them down a 1/2 hour after shift ended. Mechanics started them up and shut them down. Jim

Feb 23, 2009 | 04:25 PM

ron's power stroke

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From: White Mnt's,New Hampshire

the oil temp is what tells the PCM idle speed,, the colder it is the higher and more often it will high idle..it will also idle its self down when the oil is up to temp..i think oil temp is 180..this is so the oil will always flow thin and not starve the HPOP it also helps keep moisture out of the oil..

Feb 23, 2009 | 10:02 PM

aldridgec

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From: Wake Forest, NC

Cold weather operation is under 167 F oil temp and 45 F intake air temp. The EBPV should close during light load conditions up to those temps, and the idle will be increased up to 1300 rpm. I believe the time at idle before it will increase idle speed is 2 minutes and it must be in park, with no service brake pedal application.