Reducing radiator air flow during winter

[Backstache]

My 7 mile commute to work in the morning consists of basically 35mph for the entire drive, and these past couple of weeks up in Michigan have been pretty cold. I'm finding that my car doesn't really get up to operating temp until the last mile or so of my commute, and the cabin doesn't really get comfortably warm until I'm pulling into the parking lot. I don't believe it's a thermostat issue, the coolant gets about 3/4 of the way to operating temp after a few miles, and then it seems like the thermostat opens and all of the cold coolant in the radiator over cools the engine and it takes the rest of the trip to get to operating temp.

When I used to drive 55 miles one way to work and my car sat in a garage all night, this was never a problem.

So I made a cover for the intake on the bottom of the bumper cover to block a lot of the airflow into the radiator. I left 1" open on each side for a little airflow. The top two grills appear to be non-functional. I tested it out this morning when it was 10 degrees out and the car reach operating temp after about 4-5 miles, which is an improvement especially considering that this was the coldest morning so far. I then drove around town for 30 minutes after work in 20 degree weather and the coolant temps looked fine.

So, bad idea or completely fine? I'm keeping some side cutters in the car just in case it warms up and I need to take it off.

 

[Chris142]

The bad news. You also cut off the air flow to your AC condenser. If the compressor runs with the defroster or you happen to hit the AC switch you will most likely burn up your compressor. It cant run but a few seconds if the condenser cant cool it regardless of outside temp.

 

[JeffKeryk]

Maybe you need a thermostat?

 

[atikovi]

Engine block heater.

 

[Audios]

Originally Posted by Chris142
The bad news. You also cut off the air flow to your AC condenser. If the compressor runs with the defroster or you happen to hit the AC switch you will most likely burn up your compressor. It cant run but a few seconds if the condenser cant cool it regardless of outside temp.


The AC compressor isnt coming on below 40 anyway, so no worries there until springtime.

 

[Mad_Hatter]

I understand the "why" but not sure I'd go monkeying around with the airflow like that. There's the law of unintended consequences that could bite you in the butt..or not. It may just work for ya. But watch it...

 

[demarpaint]

That was something I did in the 70s to my 66 Falcon which had the worst heat in any car I ever owned. I wouldn't be doing it now, especially with the horrible commutes we have sitting in traffic. As mentioned get a block heater, or an oil pan heater, or both.

 

[PimTac]

Originally Posted by Audios
Originally Posted by Chris142
The bad news. You also cut off the air flow to your AC condenser. If the compressor runs with the defroster or you happen to hit the AC switch you will most likely burn up your compressor. It cant run but a few seconds if the condenser cant cool it regardless of outside temp.


The AC compressor isnt coming on below 40 anyway, so no worries there until springtime.





Don't you use your defroster?

 

[edyvw]

Originally Posted by atikovi
Engine block heater.

^
This.
I would not mess with air flow. Temperature is not going to stay in low digits constantly, so if it rains and cars starts to fog, AC will be needed. So, block heater!
I installed block heater on Toyota Sienna as it is seriously challenged to warm up in cold weather. It improved things a lot. However, since it got colder here and temperatures ventured into negative, I just use wife's Tiguan in the morning as that thing gets coolant to operating temperature in approx. 3 miles, and heating inside starts even sooner.

 

[E365]

I do that with my 1.0 EcoBoost Focus in Northern Minnesota. Probably the small engine size doesn't make a ton of heat. It does heat the cabin just fine though.

This is the 4th winter I've done it to and have had zero issues. Car does SEEM to get to, and stay at, full temp easier. Before this it rarely touched full temp (needle in middle of scale) around town.

I cover everything except the intercooler intake. The rest is fairly well blocked, but it's far from "sealed".

 

[CR94]

Good idea, as long as you're careful not to overdo it, or let it overheat on a relatively mild winter day---so pay close attention to coolant temperature. Besides aiding warm-up, should also reduce salt intrusion under the hood, and slightly reduce wind resistance.

Grill blocking is automated on many modern vehicles, which should take care of the risk of overheating on mild days.

I use foam pipe insulation, which is easy to yank out quickly in case of a warmish day. Driving efficiently on cold weather, the Prius hardly warms up fully at all without partial grill blocking, no matter how long the journey.

 

[2010Civic]

Totally fine. I've done it before on a 95 and 98 Civic. The guys not in the far north don't understand how cold it gets in the winter. There definitely isn't any rain during the winter! Lol

You aren't going to burn out the ac compressor by blocking part of the grill.

 

[edyvw]

Originally Posted by 2010Civic
Totally fine. I've done it before on a 95 and 98 Civic. The guys not in the far north don't understand how cold it gets in the winter. There definitely isn't any rain during the winter! Lol

You aren't going to burn out the ac compressor by blocking part of the grill.

I lived in MI, it will rain and you can always get those freaky warm days.

 

[2010Civic]

Originally Posted by edyvw
Originally Posted by 2010Civic
Totally fine. I've done it before on a 95 and 98 Civic. The guys not in the far north don't understand how cold it gets in the winter. There definitely isn't any rain during the winter! Lol

You aren't going to burn out the ac compressor by blocking part of the grill.

I lived in MI, it will rain and you can always get those freaky warm days.


Well it doesn't rain in MN during the winter. Either way I'm not sure why it would matter.

It was 1 degree F here the other morning.

 

[Hall]

Originally Posted by 2010Civic
Totally fine. I've done it before on a 95 and 98 Civic. The guys not in the far north don't understand how cold it gets in the winter. There definitely isn't any rain during the winter! Lol

I see vehicles, usually pickup trucks and even semi-trucks, with cardboard blocking their radiators in the winter all the time.

 

[Hall]

Originally Posted by atikovi
Engine block heater.

That only helps keep the oil and coolant warmer while the vehicle sits. The OP said the temperature reaches 'normal' after a few miles.

 

[Backstache]

Originally Posted by edyvw
Originally Posted by 2010Civic
Totally fine. I've done it before on a 95 and 98 Civic. The guys not in the far north don't understand how cold it gets in the winter. There definitely isn't any rain during the winter! Lol

You aren't going to burn out the ac compressor by blocking part of the grill.

I lived in MI, it will rain and you can always get those freaky warm days.


For sure...could be -14 one week then in the 40's or 50's the next. I would for sure be taking this off in that case. Just a couple of zip ties holding it on.

 

[demarpaint]

Originally Posted by hallstevenson
Originally Posted by atikovi
Engine block heater.

That only helps keep the oil and coolant warmer while the vehicle sits. The OP said the temperature reaches 'normal' after a few miles.

It also aids in cold starts, and shortens the time it takes the oil and coolant to reach operating temperature. Win win.

 

[4WD]

^^^ Yep … that's how the air gets dehumidified ^^^

 

[ffhdriver]

I guess the OP could not get heated seats.