Grill blocking (New to a Prius)

I block the lower grille entirely, run some foam along the hood edges inside, then push the ECO button. That's it for winter preparation for me, here in Minnesota.

In the extreme deep freeze, I'll block half of the top too. But that's mostly due to having the plug-in model, since that doesn't generate as much heat and it goes quite a bit longer between engine warming cycles.

btw, I take off the plate while squeezing in the foam insulation between the slots. It only takes a minute to remove... just 2 screws.

 

If you're running the heat, that'll make the coolant temperature drop like a rock, regardless of any grill blocking you might be doing. Of course, dropping quite a bit is no big deal; I forget when the engine will kick in just to produce heat, but up until that point, you're not really losing anything by having the coolant on the chilly side, as long as you made it past 70°C in the first place to get into Stage 4 of the warmup cycle.

 

Patrick said: After reading about the MG1 and MG2 info. I remember reading that both are in the same area and you only need to watch one of the two for temps. So I watch MG1. MG1 temp never went over 155f.

I would advise you to monitor MG2 temperatures for a while, the reason being MG1 is water-cooled and MG2 is not.
MG2 is air-cooled.

 

what are you smoking ???

Both MG1 and MG2 are in the CVT (also know as transmission) housing swimming in the same oil which I think is partially watercooled (some little channel goes through the housing ..).

anyone has that schematic ? I think I saw it here on PC.

 

@szgabor:
No, I was not smoking pot..
sorry,
I could not load "the link" to the Japanese site, I am pretty new here, not enough credit yet.
below on the picture; you can see the air-cooled note next to MG2

You know, the Prius c /Toyota Yaris Hybrid, P510 Transmission has no longer water-cooling at all, just air and circulating transmission oil.
I have a Yaris Hybrid and realy need to watch MG1 and MG2 temperatures well with the use of a grill block.

 

Patrick, when the ICE doesn't run there's nothing to heat the coolant. As already mentioned, at 150F (70C) it's warm enough for cabin heat.

Inverter coolant temp is available as an XGauge.

I set the CC on AUTO at the lowest comfortable temp in the winter & the highest comfortable temp in the summer.

 

^ Just editorial comment: you didn't mean to say CC?

 

CC in this context is Climate Control.

 

Ahh!

 

sorry but this was posted on the 3rdGen Prius forum so I assumed you are posting about that model ... but if they are in the same oil how much their temp could be different. Surely dynamic temp spikes are possible but those would occur in water cooling scenario as well !!!

Also if they are NOT water cooled ... how the grill blocking would affect them? Really worth some investigating but I do not think it makes much of a difference. The CVT is not in the direct air flow from the grill in any case.

 

Could someone explain the benefit of blocking the grill? It seems about as smart as poking holes in condoms.

 

Retaining heat gets the ICE up to temp faster & helps keep it there. The benefits are increased fuel economy as the ICE doesn't run as long just to warm itself it and more cabin heat sooner. It does prevent some damage to the radiator fins.

 

And as to the "poking holes in condoms" part... The grill is designed to provide sufficient airflow such that in the hottest location the car is likely to be used, it is not likely to overheat. When the ambient temperature is cold, it doesn't need so much air, but it gets it anyway.

Built-in grill blocking ("active grill[e] shutters") are a feature on a number of recent car models, from eco models to sports cars to luxury cars. In those cases, they're usually going for improved aerodynamics, however - the Prius can benefit from both reduced drag and faster warmup.

 

I've had my 2009 Gen II Prius for just over a year, and I've blocked the lower grill for each of the past two winters. I have a ScanGauge II and so am able to monitor the ICE coolant temp - which is normally around 190ºF, the blocking helps the system get to that temperature quicker, but the highest I've seen the temp is 196ºF. A couple of weeks ago during a particularly cold snap here in the North East, while on a run where the temp was normally ~190º, I noticed it barely got up to 170º, but that's about what I expected. Here's a pic. (regular ½" pipe-lagging from Home Despot ($4) , and zip-ties at each end) - hope this helps - Wil

 

I've been thinking about blocking the lower portion of my grill as well. What material are you using to block yours?

 

Here's a pic. (regular ½" pipe-lagging from Home Despot ($4) , and zip-ties at each end) (…is there an echo in here? …
echo in here? …echo in here?…echo in here?…echo in here?)

 

Does the Gen III Prius have a coolant thermostat in addition to an electric water pump? I would think a thermostat is unnecessary if the pump speed can be controlled directly. Has anyone observed the coolant pump running harder or more frequently due to grill blocking?

I'll probably block the Prius this weekend.