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-   -   cold start/rpm (http://www.jeepgarage.org/f73/cold-start-rpm-69998.html)

Chunderboy 01-04-2014 11:29 PM

cold start/rpm
 
How long do you guys wait to drive her after you start the rig and the rpms drop to around 1k?

berk483 01-05-2014 02:13 AM

Re: cold start/rpm
 
Once it drop below 1K rpms. There really isn't any good that comes from letting a stationary (gas engine) vehicle warm up beyond that point...except personal comfort. Unless I'm clearing snow or ice off I usually start it when I walk up to it and by the time I get myself situated and my seatbelt on the RPM's are below 1K and I put it in gear and go.


Granted I don't hammer on it while it is under normal operating temps but normal driving is fine.

MoparKing 01-05-2014 05:56 AM

Re: cold start/rpm
 
I usually wait until the engine oil temp is around 140 before I drive off, by then the rpms are low

Jim_in_PA 01-05-2014 10:54 AM

Re: cold start/rpm
 
Unless I used the remote start...make that "remembered to use the remote start"...I don't really "wait" to drive off. But I also drive conservatively and am not revving the engine.

Chunderboy 01-05-2014 11:42 AM

I usually wait till the rpms are down to about the 1k mark too. In the winter months I usually wait a little longer than in the summer.

tomk 01-05-2014 05:11 PM

Re: cold start/rpm
 
Never waited for the RPM to drop on my '07.

The computer does the right thing when you go into gear, it isn't like the old days when you'd be slamming your drivetrain. The only warming up the transmission is getting is frictional; IIRC neither the WK nor WK2 has a radiator-tank trans cooler, and even then that does no warming until the engine thermostat opens.

Drive gently until you get up to operating temp, but other than getting cabin heat there isn't much of value that happens after the first 5 seconds of engine warmup. IMHO, of course.

...tom

fun2drive 01-05-2014 05:37 PM

Re: cold start/rpm
 
Once the engine is running smooth regardless of rpms I drive off easily. Just like I don't like to get up early in the morning none of my cars and trucks take well to it either. Easy does it for a few miles then you are good to go.
Manufacturers deliberately run the rpms high at initial start to get the cats hot faster...

2014RedHemiGC 01-05-2014 06:22 PM

Re: cold start/rpm
 
Quote:

Originally Posted by tomk (Post 955104)
The only warming up the transmission is getting is frictional; IIRC neither the WK nor WK2 has a radiator-tank trans cooler, and even then that does no warming until the engine thermostat opens....tom

The new 8 speed benefits from a "thermal management unit" to help bring temps up quickly.

http://courses.chrysleracademy.com/M.../Reference.pdf


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