Warming engine up.
 

My engine (v6) takes forever to warm up. I don't work that far from home and by the time I head into work, my truck still is not fully warmed up.
Granted it is 20° out. However I usually have the engine running for a total of 45 minutes. Probably 35 minutes idle and 10 minutes driving.

Should I put some card board in front of the radiator or something?

I feel for you but cardboard in front of the radiator isn't really going to help much.... The radiator really isn't in the loop until the engine is warmed up past the thermostat rated temp (180F or so) so would not be much help here. The only thing I can think of that might help you would be a block heater...

OK, unfortunately living in the city/apartment, running an extension cord out to the street is not an option.

I am just surprised at how long it actually takes for this motor to get to normal temperature.

I even take it on the highway for approximately 1/2 a mile. Maybe I'll start taking a longer way to work.

Your thermostat could be stuck open.

Most likely cause. We have been around 0° to -9° lately. I'm pushing heat in 2 miles.

Agree with the thermostat comment. If stuck open, engine is cooling when it doesn't need it.

35 minutes idle, I literally have NEVER heard of someone keeping it idle that long. wow.

The 4.0 does take longer to work it's way up to normal operating temperature when it's really cold outside than any other vehicle that I've ever owned. I think it's the aluminum block, but who knows.

I get heat coming out of my vents pretty quick, but it takes a while to come up to full temp when it's really cold. The first cold snap that hit after I bought the 4Runner really highlighted how long it took when it's really cold. I thought that my thermostat was stuck open. I was so sure that I didn't even bother testing it, I just replaced it. The old one wasn't broken and the new one didn't change a thing. It's just how this engine works.

With all of that said, it may be your thermostat. It's certainly something to look into. But then again, there may not be a problem at all.

35 minutes of idle seems excessive, but to each their own.

I would check the thermostat or fan clutch/engagement.

long warm up time
 

If the thermostat is stuck open, this may be a good time to flush the coolant (at a shop you trust). Is the temperature gauge in normal range? I usually let my 3.4 idle for probly 15 mins when really cold ( remote start)

It's always going to take a long time to warm up at idle because that puts very little resistance on the engine. I'll let my rig idle for maybe 10 minutes some days when it's down in the single digits and the temp gauge will only move a little bit, but once I flog it up the on-ramp to the highway it warms right up.

This is a great point for OP to consider.

My civic idles 5-8 minutes and the temp gauge barely moves.

Drive it around a few minutes at 30-40MPH, and you have melting warm air blasting and temps at normal.

When the thermostat broke on my '88 Ford F150, it was in the closed position.

And of course I had to have some $30,000 of company test equipment in the back of it and it was like 90°F outside. So I turned off the AC, threw on the heat, opened the windows, and went about company business. When I got to a traffic light I would stop the engine.

Wife said my face looked pretty red when I came home.

I wouldn't let it idle for that long...these engines warm up when you drive. I let mine run for about 5 min and drive 5 miles to work...it's MUCH colder where I'm at but mine still isn't warming up...by the time I'm ready to turn it off the heater finally feels nice...if it rarely gets up to temp while driving more than your 10 minutes, it could easily be your thermostat...which DO go and need replaced...

Sounds like the thermostat is stuck open. My V6 warms pretty quickly even when it's really cold out. I will say that my 4th gen does warm quicker than my 5th gen though.

Dress in layers, wear gloves...youll be fine