I have a few questions...

1. it is about 0 degrees here in chicago and i am running a 160 stat with about 70% water to dexcool. it seems to run at about 170 degrees while cruising..is this to low? pros and cons of running this cold

2. what exactly happens when i turn on the heat? (fans/heater core etc..) what actually happens in my engine? i would like a good idea of what happens surrounding the heating system.

3. say i drive around for 30 min (so shes warmed up nicely)..i start the car and it idles nicely...then i drop it down to gear and the rpms drop to almost 250-300 but NEVER stall then go up to normal right after? huh? Also the warmed idle in gear is about 400 but steady n strong

4. i left my car out in the below zero cold last night and it was a hard start?..also my belt was screaming for a while on startup..

5. my volt gauge reads almost to the red (18) on startup but goes down to just below 3/4rths tick so like 15-16 during driving...it used to stay at middle tick

Thanks to all

 

1. It may freeze with 70% water, no harm will come from running at 170 but in theory you won't get the max potential from the car (a few less horse power)

2. When you start the car it generates heat as a byproduct of friction, therefore the coolant heats up, once the coolant reaches a certain temperature (thermostat rating) the thermostat will open up and allow the coolant to flow throughout the entire cooling system. When you turn the head on you open up doors on the heater box which houses the heater core, with the heat flipped on the blower fan starts to spin, it pushes air across the hot heater core making heat come out of the vents.

3. My car does the same thing, it's just something automatics due when you put them into gear.

4. Hard start as in extended crank or it just cranked slowly? Check the battery state of charge, the belt it most likely due to the cold but check it's condition (cracks, rips)

5. Never had it happen so I can't really help you there.

 

Answers:

2. When you turn on the heat, a vacuum-actuated valve opens, allowing hot coolant to flow into the heater core, and the blend will open to allow air blown by your blower motor/fan to flow across the heater core. Your heater core is a heat exchanger and works the same way your radiator does.

5. I'm assuming that your voltage has been spiking up like this since it got cold? A cold alternator will show more voltage on your gauge. Electrical parts are effected by several things, one of them being heat. As the alternator spins and the engine warms up heat builds in the coils of the alternator, lowering the voltage output. Nothing to worry about unless it stays pegged out at 18 volts.

The other questions were answered by Kataklysm, but I don't know what your coolant/water dilution should be in that cold of weather. Having only owned cars in FL, I just always stick with 50/50. I would think you want to get closer to that ratio than the 70/30 mix you have right now, but once again, double check me on that. Or somebody who lives somewhere it's actually cold could post up.

Abe

 

thanks guys this is all very helpful...so when i turn on my heat, are the fans actually making my car run cooler since they r blowing? or is it just blowing over my heater core/engine rather than radiator

 

also i have an aftermarket lid w no provisions for the AIR pump tube..so it is basically just hanging there with no filter..could this be a vacuum leak or anything? cause low idle?

 

With the heat on the blower fan inside the car is removing a little heat since the coolant is circulating through the heater core - but not that much.

No filter on the air hose won't affect idle/cause vacuum leak. I'd get a cheap filter for it though and zip tie it off somewhere.

 

That voltage is too high. I bet your regulator is shot. Too high a voltage can fry a lot....

 

Your cooling fans (big fans behind radiator) do not turn on with the heat. There is another little fan inside your heater box located in the dash behind the glove box. That is the fan that turns on and blows the air across the heater core to produce heat. So no, your car isn't running any cooler.

 

Dexcool should only be used as a 50/50 mix.

 

Up here in New York i usally run 60% antifreeze, 40% water. Dont ask me why its just something i picked up from my dad, but i never have any problems.

 

I have actually seen cars with cooling system problems that prevented catastrophic overheating by turning on the heat at full blast. But this is an extreme case, and I don't think you're going to see a difference in operating temperatures under normal circumstances. Besides, your thermostat always opens at the same temp and your fans always come on at the same temp (hopefully!) so except maybe on the highway at 70+ mph, turning on the heat wouldn't change your operating temperature. Plus you have an '02, so you wouldn't know it anyway! Just to clear it up, the fan that turns on is your blower motor fan, which is, as stated above, in the box behind your glove box. The radiator fan(s) only turn on when the A/C is turned on.

Abe

 

usually when i turn the heat on, i am going 70+ on the highway in below zero weather

 

Your best bet is to mix your DexCool 50:50 and don't worry about the other stuff, unless the voltage never goes down to normal. Yeah, turning on the heater does lower the operating temps a little, like said above, and can prevent some damage in a severe overheat, but you WILL NOT be able to tell a difference in normal driving. How do you know you are running at 170 anyway? You have a 2002 with a dummy temp guage. And put a filter on the AIR tube...thats just sloppy, and it really tells a lot about you and your car, IMO. Seriously though, take some pride in what you do. It won't hurt anything, but get it fixed.

 

Also, its not below zero in Chicago right now, and you probably shouldn't be doing over 70 if it is anyway.

 

"Also, its not below zero in Chicago right now, and you probably shouldn't be doing over 70 if it is anyway."

You should come sometime

"And put a filter on the AIR tube...thats just sloppy, and it really tells a lot about you and your car, IMO. Seriously though, take some pride in what you do. It won't hurt anything, but get it fixed"

ok mom

Heres some pics of my pos that i dont take care of


http://i14.photobucket.com/albums/a...y8/P1010430.jpg
http://i14.photobucket.com/albums/a...y8/P1010422.jpg
http://i14.photobucket.com/albums/a...y8/P1010452.jpg