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Cold weather start, with and without block heater

10431 Views 6 Replies 4 Participants Last post by  zoomie
The weatherman predicted -18c / 0f for this morning so I plugged in the engine heater for the first time. I used a timer that came on at 4:00am and was on for 3 hours before I came out.

With the heater the truck started like it was summer time. No delay at all. The water temp was 40c / 104f, The tranny was -9c / 15f. The engine was real smooth but the tranny shifted a little late however it warmed up very fast. It was 0c / 32f in just a couple of minutes of easy driving.

I have started it at close to this temp before without plugging it in and after I turned the key, it did it's warm up thing then started up. About 3 second delay. Then you have a very cold engine running. Is smoothed out right away but you could tell it was cold.

So I've started very cold with and without the engine heater. I have to say that I'm fine with the inconvenience of plugging it in at night if it's going to be that smooth right from the start in the morning. Saves warm up fuel too.

There are a lot colder places out there, but this is my experience.
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Update : -18C again this morning but I reduced the block heater time to two hours. Water temp was still at 40C at start-up.
Must be a decent block heater in this Ram. This engine takes a life to warm up the coolant when running. You might be saving 3-4 mpg during the first 15-20 minutes on average potentially with daily block heater use. Are you going to find the minimum on time to reach 40 C with -18 C ambient? That would be great data!

The defrost and cabin will get warm within minutes after a cold start due to the 900 W PTC heater in the HVAC system. Think of it as the heater in a hair dryer. The high idle most likely compensates for alternator load (steering wheel, seats and PTC heaters are pulling several amps.)
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