Better to let run before shutdown?

It is definitely a thing with gen 3. Shutting down after a brief run can leave condensed water in the skinny EGR passages, and then on the next start the engine will bang like the hammers of Hephaestus for a long moment before smoothing out.

I haven't heard the same thing about gen 2.

But never mind all that, you don't need to start the engine at all to roll the windows up. You can just go to IG ON (two button pushes without brake), roll the windows up, and switch the car back off (one more push, no brake). No going READY, no starting the engine, no waiting.

 

For 20 years you have been making exposure to deadly poisons worse for you and your loved ones. Here's 3 different reasons for why you need to stop doing that!

1) Long ago you needed to warm up a car engine, especially big trucks in cold weather because it took a while for the oil pump to get everything in the engine well lubricated... But as time went by and engines got more modern you no longer had the need to wait on lubrication to optimize.

2) Another reason people used to wait for the engine to warm up is because you needed the intake manifold and carburetor to heat up to better vaporize the fuel so the engine worked normally. When Fuel Injection came along in the 80's waiting for it all to heat up was no longer necessary.

3) "Existing literature, as well as analytical tools like the U.S. Environmental Protection Agency’s Motor Vehicle Emission Simulator (MOVES), indicate that while total vehicle emissions have dropped significantly in recent years, those associated with cold starts can still constitute up to 80% for some pollutant species. Starting emissions are consistently found to make up a high proportion of total transportation-related methane (CH4), nitrous oxide (N2O), and volatile organic compounds (VOCs). After 3–4 min of vehicle operation, both the engine coolant and the catalytic converter have generally warmed, and emissions are significantly lower." https://www.sciencedirect.com/science/article/abs/pii/S1361920915002229

and

"Toxins released during cold starts

• Benzene: A known human carcinogen and neurotoxin, benzene is present in gasoline and emitted during incomplete combustion, according to ScienceDirect.com and the Colorado Department of Public Health and Environment (.gov).
• Formaldehyde & Acetaldehyde: These are air toxins and volatile organic compounds (VOCs), which can contribute to respiratory issues and other health problems.
• Carbon Monoxide (CO): A colorless, odorless, and highly toxic gas that can restrict the blood's ability to carry oxygen and lead to serious health problems or even death.
• Nitrogen Oxides (NOx): These pollutants contribute to smog and can cause respiratory problems.
• Particulate Matter (PM): Fine particles released during combustion that can penetrate deep into the lungs and cause respiratory and cardiovascular issues.
• Volatile Organic Compounds (VOCs) and Intermediate VOCs (IVOCs): These organic gases are important precursors to secondary organic aerosols (SOAs), which have adverse impacts on air quality and human health."
• 
  From: https://www.sciencedirect.com/science/article/abs/pii/S0304389422007683

 

She's said she no longer drives a Prius in previous posts... If she was still driving a Prius she could roll up the windows and be done with it before the engine even started.

As for water in the EGR passages that would be a problem on a car that's rarely driven, but that line of thinking seems like nonsense if its a daily driver.

 

For gen 3 it has been a nuisance known from the earliest days, with the first reports rolling in around October 2009 for spanking-new 2010 model year cars, only on a next start after a short no-warm-up run followed by a cold soak, with Toyota's response a couple years later in January 2012.

Water in the EGR passages isn't any great mystery, given that those passages carry ... exhaust, which is 13% water. It's usually there; I poured a noticeable amount of clear water out of mine when I cleaned the system.

Only, for it to fill the passages enough to be snorted into the intake on the next startup, it seems to take a short, no-warm-up engine run followed by a good while sitting cold.

 

Looks as if Kris' "let it run" mantra has some merit at least sometimes with the right rig, such as G3.

But I suspect her dad was was talking about less exotic rigs and if it was a good idea then, is it still smart to let it run a bit?

As a WAG, IT may have some merit,but...?

This would had been a great question for Tom&Ray on CarTalk. Heck, they may have covered it.

https://www.cartalk.com/

 

.

 

They actually did... It was a hilarious husband and wife dispute.... I'm not able to dig that recording up but CarTalk laughed and told jokes like they always do and they were 100% on the side of start your car up and drive away (but go easy on driving it as it warms up) ---> minimize poisons to family and neighbors! Cold engine air pollution is highly toxic!

 

.

 

Drunk posting?

 

^ Usually.

At the risk of actually answering the OP it's OK to roll up the windows without starting the car - in fact, it's probably better than starting the car to do so - but mostly???
It's a difference without much of a distinction.

This isn't 1930, and even marginally built cars will last well over 100,000 miles under normal use which will certainly include a few short start/stop cycles.
Oil is a little bit different too which is the reason for the overly long oil change periodicities that the OEMS use.

Priuses have criminally small aux (12vdc) batteries - and they mostly can get away with it because they do not have separate engine start motors.
EVEN IN A PRIUS, if your aux battery dies because you use it to roll up your windows you didn't CAUSE a problem you DETECTED one. Most other cars these days still have two things that will probably be with us for a while longer.
Start motors for ICE cars and inept government regulation - in case you're not familiar (or cursed) with the auto-stop-start (A.S.S.) feature.

This means that normy cars are ALSO going to be forced to have adequately sized 12vdc batteries - at least for a while.
In my never-to-be-humbled opinion?
You may as well use it to roll up the windows.


MY mileage.
Yours will undoubtedly vary....

 

These are significant electrical loads on the 12 V battery:

• Window motors - have a high current load. Brief but significant as shown by the fuse rating in your car fuse box.
• Starter motor - often measured close to 100 Amps, starting the engine needs to run a minute or so for the alternator (formerly generator) to replace the charge on the battery.

If you have a weak, 12V battery, operating the window motors could deplete it enough there might not be enough charge to start the engine. But if the engine starts first, in a minute, the starting current load will be replaced and the alternator can immediately handle the window motor current.

IMHO, as long as the battery is not over 5 years, just turn on the ignition and close or open the window. If you are trying to stretch a weak battery, start the car first. If it starts, no problem. If it doesn't, get a battery jump and get thee to a parts store.

Back in the day when headlights were incandescent, you could turn them on and see how badly they dimmed as a crude battery health check under different loads. Of course that was when I had hair.

Bob Wilson

 

The one time it most irritated me was when I was searching for a spot in a very full parking garage and I saw someone walk to her car and get in. The lights came on. The car started. I waited. The car blocked behind me waited. The car blocked behind that car waited. At the point when there were about six cars blocked behind me, I got out of my car and walked up to the one in the spot and asked whether she was planning to leave that spot at any point, and she said "sure, as soon as my engine warms up".

She was in a Prius.