Remote Start

I'd be surprised if anything remotely recent did that. I mean, if whatever kind of heat-exchanger this system used was to fail, the heater would literally be sucking exhaust gasses into the car!
 
Er.. No. The heat from the heater matrix is generated by the coolant flowing through it. It's pushed into the cabin by the fans. If the engine isn't warm, you won't get any hot air. If your car is sitting idling for 10 minutes, it won't be nearly as warm as it would if you've been driving it for 10 minutes.

Which is what I said. In order to get the car warm quicker, get moving. The heater matrix requires airflow as well as the blower, hence why the blower is almost ineffective at idle and slows down the time the engine takes to warm up.

Get driving, blower off, the engine warms up even quicker again :)
 
An idling engine doesn't warm up very quickly, so all the wear conditions that are associated with a cold engine are maintained for longer e.g. low oil flow, rich mixtures causing bore wash coupled with larger piston/bore clearances giving increased blowby and oil dilution etc.

this has always been my understanding.

For all the advances in modern oil technology, you are still advised against thrashing an engine from cold because its not fully protected yet.

Leaving the car running at idle just extends the period it spends cold and wearing the engine more than at warm temperatures.
 
Which is what I said. In order to get the car warm quicker, get moving. The heater matrix requires airflow as well as the blower, hence why the blower is almost ineffective at idle and slows down the time the engine takes to warm up.

Get driving, blower off, the engine warms up even quicker again :)

Sorry, I misunderstood what you said a bit!
 
Which is what I said. In order to get the car warm quicker, get moving. The heater matrix requires airflow as well as the blower, hence why the blower is almost ineffective at idle and slows down the time the engine takes to warm up.

Get driving, blower off, the engine warms up even quicker again :)

Your climate control unit shouldn't push any air at all into the cabin until the heater matrix can provide enough heat to heat the air to the required temperature.

If that happens through 10 minutes of idling on the driveway or 3 minutes of driving then so be it, but to say that the cabin heating systems are ineffective solely because the engine is idling is absolute hogwash.
 
Your climate control unit shouldn't push any air at all into the cabin until the heater matrix can provide enough heat to heat the air to the required temperature.

If that happens through 10 minutes of idling on the driveway or 3 minutes of driving then so be it, but to say that the cabin heating systems are ineffective solely because the engine is idling is absolute hogwash.

ah is that why when I hit 'auto' in my car it turns off the fans?

thought it a bit odd, dial in 28c (or whatever) and whack up the fan and it blows away like a dutch prozzy, if you hit auto it just turns off then goes mental about 5 miles down the road! - presumably once warmed up?
 
Your climate control unit shouldn't push any air at all into the cabin until the heater matrix can provide enough heat to heat the air to the required temperature.

I can confirm that the climate control in Luceros car will not allow any airflow into a cold cabin until it can provide warm air :p
 
I've always considered leaving a cold engine idling to display a lack of mechanical sympathy in the same way that hearing my colleague revving his bike hard at startup makes me wince.
I (would imagine) it's a fairly uncontested view that engine wear due to cold oil is more significant when the engine is cold. If that is the case then the quickest way to get the engine temperature up to normal levels would be to drive it whilst keeping the revs low.

And aside from the security implications, it it not illegal to leave a car engine running if the vehicle is unattended?
 
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I'd be surprised if anything remotely recent did that. I mean, if whatever kind of heat-exchanger this system used was to fail, the heater would literally be sucking exhaust gasses into the car!

I guess it was exhaust to coolant.

Ie just like an EGR cooler on modern diesels, or indeed Prius 3 has a heat exchanger in the exhaust to heat the coolant. Prius 2 had a 3 litre vaccum flask that stored hot coolant at engine off so it was ready for restart to heat the engine faster.
 
Which is what I said. In order to get the car warm quicker, get moving. The heater matrix requires airflow as well as the blower, hence why the blower is almost ineffective at idle and slows down the time the engine takes to warm up.

The heater matrix is a radiator, as in water to air, it doesnt require airflow. To provide heat to the cabin the blower does that by drawing air through its core.
 
The heater matrix is a radiator, as in water to air, it doesnt require airflow. To provide heat to the cabin the blower does that by drawing air through its core.

Hold on wut?

It doesn't require airflow, yet it provides heat by drawing air through its core. That would be airflow then. A heater matrix also takes natural airflow whilst a car is moving. Hence, older cars will supply heat to the cabin if set to hot regardless of whether the blower is on or not. If you're not moving and your blower is off, there is no airflow. If you're not moving and your blower is on and your engine is cold you are pulling any heat from the engine immediately into the cabin and it will remain cool / warm until the engine properly warms up.

:)
 
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Hold on wut?

It doesn't require airflow, yet it provides heat by drawing air through its core. That would be airflow then. A heater matrix also takes natural airflow whilst a car is moving. Hence, older cars will supply heat to the cabin if set to hot regardless of whether the blower is on or not. If you're not moving and your blower is off, there is no airflow. If you're not moving and your blower is on and your engine is cold you are pulling any heat from the engine immediately into the cabin and it will remain cool / warm until the engine properly warms up.

:)

NO car I have ever been in will supply hot air (to any noticeable extent) to the cabin with the blowers turned off. That is the point in them being off.
 
NO car I have ever been in will supply hot air (to any noticeable extent) to the cabin with the blowers turned off. That is the point in them being off.

I beg to differ there, my missus saxo is good as you can have the blowers off but still get a sense of the heat inside, obviously not as much as if the blowers are on but you do. Sometimes have to turn it dwon to the colder side so your not too hot.
 
really, I can name a lot. Pretty much any car with a manual blower will supply warm air if the vents are open, set to hot and the blower is off. By your own admission you say to any noticeable extent, sure it's not going to be like a log fire, but its warmth none the less. Will it heat a cabin, no, but the airflow over a car whilst moving will push warm air from the engine into the cabin. It's not that hard a concept to grasp.
 
really, I can name a lot. Pretty much any car with a manual blower will supply warm air if the vents are open, set to hot and the blower is off. By your own admission you say to any noticeable extent, sure it's not going to be like a log fire, but its warmth none the less. Will it heat a cabin, no, but the airflow over a car whilst moving will push warm air from the engine into the cabin. It's not that hard a concept to grasp.

From the engine? What? Engine heat transferred to the heater matrix via the coolant, or just warm air blown through the engine bay?

If you mean the latter then... just lol...

I meant by that that the vent plastics wouldn't even be warm.
 
I've got remote start on my Civic Type-R, and in this weather it's awesome. Can start it 5 mins before I leave work and get in to a warmed up car. :D

Any properly installed remote start system won't activate unless the car is in a state where it can't possibly be in gear. On mine for example I have to leave the car with the engine running and close all doors (so impossible for the car to be in gear), if I open a door again it won't activate. The only way my car could be in gear when the remote start activates is if I locked someone in the car who put it in gear after I'd left it.

Regards "engine damage by idling" - why wouldn't manufacturers have an auto kill-switch in the ECU if the engine is left running whilst stationary for too long, if it was as big a problem as some people make out?
 
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