Hood insulation?
 

Does removing hood insulation reduce underhood temp or will make it worst?

I guess it depends on how sunny it is. I don't know, but that insulation is meant to act as a fire retardant in some cars. In case of an angine fire, the plastic fasteners melt, and drop the insulation. It then, at least partly, smothers the fire.

I doubt the risk would keep me from removing the insulation, if I felt that would help in whatever issue you are having, but it's better knowing all the ramifications of doing something.

It may also have an adverse affect on the paint on the hood.


YMMV

Can make the car louder too. Engine noise does go through the hood and then the windshield. Sound deadening in the hood is usually a good first step in noise reduction.

90% of the time it's sound insulation. I've seen plenty of cars with it removed for years without bothering the paint. parking it in the sun will bother the paint more. it may reduce underhood temps a little but once the engines running, there's enough airflow it won't bother it much.

My car never had any to start with...

I'm guessing it would have only a small effect on underhood temps, however, for those runs into the store, having the insulation in place may keep the engine warmer for when you restart it.

I've got a large piece of corrugated cardboard from a box covering the top and two sides of my engine to help it maintain temps.

Does it help?? maybe. I live in a 9000 DD climate and will take any advantage when it's -20F. At that temp, the hell with mileage, I just want the heater to warm up!

I do not believe it will change under hood temps. I would keep it though for fire protection and paint protection.

Is the underside open between the bumper and the front of the radiator; that could be blocked. Where is the air intake getting air; warmer air under the hood would warm quicker than a cold air intake from outside the engine bay.

Ahh yes,,, another reminder of future projects I have yet to accomplish!!!;)

Obviously these entail more work than throwing a piece of cardboard over the engine, and I may do them this summer. Right now I have the back of the grill blocked with some Coroplast, and the idea of a bellypan/engine compartment block is appealing. AFA the air intake I do have it drawing from the engine compartment, no special ducting though.

I'm pretty happy with the 40 MPG I'm getting on a 06 corolla with an AT, but yeah, I could do more.....

Most cars don't even have the insulation. Out of all the ones I've owned, one has had it, and it fell apart in the end anyhow.

With or without it, it will make little difference. I'd probably remove it to save some lbs.

Mine doesn't have it either, although everything else I've owned did have the insulation. Haven't really noticed a difference either way.

It's funny you say that, because all of the cars I have owned (except hondas) have had them, most were in the process of falling out though.

I would imagine the only mpg advantage these can provide, is a slight amount of thermal insulation for the engine on short engine off stops. I was browsing around an insight forum, and they actually had lovely coat like things made for their engines. That would be the way to go, way less noise, and much faster warm ups. Early sensor death though?

If you want to help your engine warm up and maintain heat in the winter put a piece of cardboard in front of your radiator to keep the air from going through it cooling the water.

i saw a on youtube on "how to hypermile" and they said to add insulation under the hood. and it looked like just a some foil and duck tape. here's the link https://www.youtube.com/watch?v=TfGFgXTpQW4
has anyone done this?