Weak heater L300

ontheebrink · Post by **ontheebrink** » Tue Feb 20, 2018 5:02 pm

I was recently up in the mountains stuck in traffic in snow and I noticed the heater wasn't putting out much heat as the motor got cold from barely working. Basically I was idling down hill for 15 miles at 25mph.

I haven't had it long so I'm wondering if this is normal or is it a problem I should look into. It was blowing warm air but nothing hot enough to warm the cab.

north54 · Post by **north54** » Tue Feb 20, 2018 7:07 pm

Might be due for a coolant flush or new thermostat. Did you have the rear heater working as well? Only the bottom rear blower will put out warm air BTW. I notice in sub zero temps here if I don't have the rear heater working as well as the front it takes a long time to heat up the cab.

Good luck.

msimps · Post by **msimps** » Wed Feb 21, 2018 9:20 pm

Fairly normal in my minimal experience. I often run both rear heater and front to get a more comfortable temp

Sent from my iPhone using Tapatalk

Shaun Van Ramen · Post by **Shaun Van Ramen** » Sun Feb 25, 2018 8:38 pm

My L300 runs dead cold in winter when going down hills, especially at highway speeds. I never changed the thermostat, but I have been running 2 different rad blockers. 1 down low by the skid pan to block the direct flow of air (especially since the cabs on these tings are so drafty - at least mine is), which I put on every winter. It seems to help a bit in the cold. This year a went the D.I.Y. route and just placed a piece of cardboard between the rads. That definitely keeps it warmer (as well as more heat in the engine) on our winter highways (in BC).

msimps · Post by **msimps** » Wed Feb 28, 2018 8:43 am

Travelled up and down the coquihalla this weekend and had to run both heaters at full temp and fan just to keep the cabin barely comfortable. Every cold gust of -20 wind (Friday was cold) could be physically felt

Naturally downhill was the coldest! Definitely a pan/windblock would’ve helped some.

Sent from my iPhone using Tapatalk

Trinker · Post by **Trinker** » Wed Feb 28, 2018 1:32 pm

You should try a rad blocker, but your thermostat could also be partially stuck open, how long does it take for your engine to warm up? I usually idle mine for about five minutes, and then it takes another five minutes of driving to reach full normal temperature. My rear heater hasn't worked since I bought the van three years ago, but even in the interior of BC winter without a rad blocker, I've never been cold while driving.