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Cold Start RPM ?

7K views 13 replies 6 participants last post by  billt 
#1 ·
It doesn't get very cold around here in the Winter. At the coldest the upper 30's perhaps. And then that's just in the very early morning hours. Once the Sun comes up it gets warmer faster.

Anyway, when I start up when it's in the 40's or 50's inside the garage, it initially revs up to around 1,200 to 1,300 RPM. It holds that for about 30 seconds before it starts dropping off, (5.7 HEMI V-8). Then after about a good minute or so it drops down to normal idle RPM of around 650 RPM. During all of this you can't "kick it down" by stabbing the throttle quickly. You have to let it runs it's course. Are you guys experiencing the same?
 
#4 ·
Mine idles as high as 1500 when cold in my V6. I'm glad you asked that question because I've been wondering the same thing. I've had mine about a year.
Actually I just checked this morning, (about 55F in my garage this morning), and it cold started right at 1,500 RPM. Then it backed down to around 1,100 to 1,200 RPM for about the better part of 30 seconds. Finally, after about 1 minute it settled down to it's normal 650 RPM hot idle.
 
#5 ·
Normal behavior. They program the engine to idle high when cold to get the catalytic converters to light off (reach a temperature where they can be effective) quicker. This is why the V6 doesn't have exhaust manifolds in the traditional sense- the cylinder head has a large square flange that the cat bolts straight to.
 
#14 ·
Not too many of those sold here in the desert Southwest. However, mine has a rear window defroster. I'm not sure it works. I've never turned it on. Hell, I've yet to run the front or rear wipers! I know the heated seats and wheel work because they came set to automatic, before I deactivated them to full manual control. $95.00 isn't bad at all. If I still lived in the Midwest, I would have one for sure. :thumbsup:
 
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