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1967 Eldorado
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Discussion Starter #1
I was just reading a post in the Seville forum about not letting the car idle and warm up for 10 mins but rather wait a few seconds for the rpm to come down to 900 and then drive. My car starts at 900-1000 and stays there until its warm and then it comes down to 600. This only happens when its 33* or lower. Also the A.I.R pump doesn't run when its that cold either. I couldn't remember the car doing this last year so I started to check things out but it doesn't seem like there is a problem so I let it go until I saw that post about the Seville.
 

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White Diamond '03 DHS (with DTS floor shift)
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The AIR pump should run for about 40 seconds or so on a cold start. RPM should start out at about 1200 and then drop to about 900 after the AIR pump shuts down. Have you checked your DTCs?
 

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2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
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It's been VERY cold here for the week or so. A few times, I've noticed my car seem to skip the 1,2000 RPM part of high idle, and the air pump does not run.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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The STS started at 900 rpm this morning - it was 19 in the garage. (No AIR either..........)

When all's right, these cars are smarter than we are..................
 

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1967 Eldorado
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Discussion Starter #6
I have no DTC's and this hasn't just started since the cold its been doing all winter when the temp is below 33 but since your cars are doing it too I will worry a little less. I'll see what my friends Deville does on a cold start tomorrow. I do like to let my car sit for a little bit to warm up though as when its cold and especially this cold it has a knock and everything just feels stiff. While I brought it up would a cold knock be anything to worry about.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Wild guess: Heating the car too quickly in extreme cold may damage it?
MOST stone cold oil bypasses all the filter media. SWAG (Scientific Wild Ass Guess) - lower oil flow to at least filter SOME oil ??? Something to study up on..............

BUT, a carbureted car always starts at fast idle, cold......................

Cold "knock" - could be piston slap or cold carbon rap - not to worry. ("Cold Carbon Rap" ??? - I assume you have read the entire Cadillac Technical Archive up ^^^ in the top black bar ...........)
 

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2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
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Submariner409 said:
MOST stone cold oil bypasses all the filter media. SWAG (Scientific Wild Ass Guess) - lower oil flow to at least filter SOME oil ??? Something to study up on..............

BUT, a carbureted car always starts at fast idle, cold......................
My post was supposed to say CAT, not car (iPhone autocorrect). My thinking was that heating the CAT quickly (the point of the AIR system) from very cold temps, may cause it to crack, or be otherwise damaged :noidea: .
 

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1967 Eldorado
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Discussion Starter #9
Cold "knock" - could be piston slap or cold carbon rap - not to worry. ("Cold Carbon Rap" ??? - I assume you have read the entire Cadillac Technical Archive up ^^^ in the top black bar ...........)
I have read there and have done many WOT procedures but no difference so when I go I take it very easy until it's gone. Usually it goes in a few blocks but with the temps lately it takes a mile or two.
 

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I have read there and have done many WOT procedures but no difference so when I go I take it very easy until it's gone. Usually it goes in a few blocks but with the temps lately it takes a mile or two.
how many times have you done WOT as to how they say its good to do it atleast twice a week and engine damage will NEVER occur because these are high performance engine's and were built to be ran like that!
 

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1967 Eldorado
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Discussion Starter #11
I haven't done any lately but I did something like 5 last spring and a lot in the fall before I had the front motor mount replaced. However I do love the Northstar and just do some short WOT when I have the feeling for the fast n furious a few times a week.(don't ask what my MPG is)
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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jounier11, WOT procedures are entirely up to you, your trust in your car, and your driving experience. There is NO hard and fast recommended frequency or procedure for maximum demand engine exercise. If you blow the engine, it's your fault ..... :lildevil:
 

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White Diamond '03 DHS (with DTS floor shift)
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It's been VERY cold here for the week or so. A few times, I've noticed my car seem to skip the 1,2000 RPM part of high idle, and the air pump does not run.
The STS started at 900 rpm this morning - it was 19 in the garage. (No AIR either..........)

When all's right, these cars are smarter than we are..................
:hmm: Never noticed that before. I'll pay closer attention tomorrow morning. Leaving early to go goose hunting, but then again my garage will probably still be around 30*.


how many times have you done WOT as to how they say its good to do it atleast twice a week and engine damage will NEVER occur because these are high performance engine's and were built to be ran like that!
:cop: Whoa! Not that this is bad advice, but I don't ever recall hearing a recommended frequency or a guarantee.
 

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White Diamond '03 DHS (with DTS floor shift)
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Left a zero dark thirty. Garage was 30-32 Degrees. Car idled at 1000 on a cold start. Can't hear the AIR pump, but I suspect the lower idle indicated no pump operation.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Begs the question: Cats DO NOT like rich fuel mixtures. Electronic fuel injection allows the engine to run with the bare minimum of cold start enrichment. BUT, extended cold idle times are not good for the engine. What damage is being done to the cars that have aftermarket remote starters installed with no fuel programming change to the PCM ? Idling for 15 minutes from dead cold while Muffy makes her latte' is death on an engine.
 

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74 Coupe DeVille, 99 DeVille D'Elegance (diamond white)
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BUT, extended cold idle times are not good for the engine. What damage is being done to the cars that have aftermarket remote starters installed with no fuel programming change to the PCM ? Idling for 15 minutes from dead cold while Muffy makes her latte' is death on an engine.
Why?
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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A cold engine, idling during warmup, tends to condense fuel vapor on the cylinder walls, washing off the oil film. There are other reasons - low cold oil circulation for one. Water condensation caused by cold air drawn in by the PCV system condensing on cold parts is another.

Most automakers and car magazines recommend that you start the car, allow the engine controls or carburetor to fast idle the engine for 15 - 20 seconds, then drive away normally. The engine warms much faster as does the oil. Don't use full power until at least 10 miles have been covered.

Your Deville and my STS will "fast idle" at about 1200 rpm for about 20 seconds or so, then drop to 900 for a minute or so, then to the normal 650. (Recently, we've seen [in here] that some of these cars seem to idle at around 1,000 when it's really cold. This may be either a PCM control function or due to cold oil drag. Anyone's guess.)

For a demonstration of cold oil, say 5W-30, pour a pint into a Mason jar, cap it and stick it in the freezer. Let it chill to 15 degrees or so. Now shake the jar. Gooey, isn't it ? You want that oil to warm as fast as possible, and light load driving does just that - safely. Just because the heater blows warm air does NOT mean the engine is properly "warmed up".
 

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1967 Eldorado
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Discussion Starter #18
Yesterday it was 33 and everything started up like normal. Today it was 32 the higher idle and air pump ran for about 3 seconds and shut off. I don't recall any this happening last year but with an almost perfect cosistinsy it must be how operation is in these cold temps.

Great information Sub I no longer start my car 5-10 minutes early to get the motor warm. I start it and sit for a minute or so then just go nice and slow.
 
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