Newsgroups: rec.autos.tech
Subject: Re: Cold Weather Rec. & General Car care
From: dave.williams@chaos.lrk.ar.us (Dave Williams) 
Date: 8 Feb 94 15:21:00 GMT

-> Let it warm up first?  That is against all the advice I've ever
-> heard.  Wait till you have adequate oil pressure, then baby it (i.e.,
-> keep the revs down) until it is warm, but by all means, do NOT delay
-> the warming up process by letting the engine idle till warm.  If you
-> keep the revs down, you are not really loading the engine, and you're
-> saving gas too.

 I have an "Ask Pennzoil" sheet where someone asked them about cold
starting.  The Pennzoil tech said that, unless the owner's manual
specificially states otherwise, to start the car, wait a few seconds for
the oil pressure to come up, and drive off, but not to dog on the car
until the water temp came up.

 Being a typically impatient American, that's how I drive anyway, but I
was gratified to see Pennzoil thought it was OK too.

From: cbm@athena.mit.edu (Charles Bruce Musgrave)
Newsgroups: rec.autos.driving
Subject: Re: Idling: Is too much bad?
Date: 6 Feb 1996 16:05:57 GMT

Yes.  Too much idling is bad.  Especially if the car is cold
to start with.  The longer it takes the car to warm up above
the vapor point for the combustion byproducts, the larger
the amount of particulate formation and growth.  This leads
to sludge, varnish and particulates in your oil.  In addition
to the wear these types of particles cause, you also end up 
needing to change your engine oil more frequently because these
get you to your oil's particulate threshold faster.

The same principle leads to the increased acids in the engine
oil, except that when acids are not boiled off promptly 
(because you idled your car to warm rather than driving it
moderately to warm it quicker) you get corrosion of the engine 
metals. 

In addition to long idles to warm up, you can get the same 
deleterious effects by taking lots of short trips.  Since it
takes time above the byproduct boiling point to boil off
all the byproducts short trips, say under 8-15 miles, especially
in stop and go driving leave a lot of gunk behind.

If you can get your hands on an engine prewarmer (they should
be pretty common up there) it is well worth it.

Charles