Any thoughts on insulating a 2004 Corolla from engine noise? - PeachParts Mercedes-Benz Forum

Mölyapina · #1 03-13-2013, 12:16 AM

Our '04 Corolla gets loud around 2000 RPM, such that it is easily noticeable in 4th (will probably be so in 5th also when I take care of a few seals

), and I'm wondering if there is any way that I could add insulation to the hood and/or firewall to tamp down the noise a bit. Both of them are insulated, but the material looks thin. I was under the impression that the noise was unavoidable, until I read a Consumer Reports review that said that the Corolla gets loud faster than others in its class. I'd like to not have to raise my voice if I want to talk to the back seat. I realize that wind noise is also a factor in this car, but I can tell the difference between that and engine noise, and the engine is a definite contributor (especially at speeds below 50 MPH).

DieselPaul · #2 03-13-2013, 01:09 AM

Dynamat or Fatmat.

Mölyapina · #3 03-13-2013, 08:05 AM

Quote:

Originally Posted by DieselPaul

Dynamat or Fatmat.

Should I worry about the insulation catching fire? Any other place to use it besides the firewall/hood?

E150GT · #4 03-13-2013, 08:45 AM

Id be interested to see how well you can insulate the car. And for what cost. Ive only driven two toyotas, a 2012 yaris and a 2005 corolla. Theyre both pretty loud. the yaris engine is surprisingly noisy.

SwampYankee · #5 03-13-2013, 09:23 AM

I'd go with Dynamat or similar like DieselPaul said. Inside the cabin under the carpet. Is it direct engine noise or is it resonance?

Simpler=Better · #6 03-13-2013, 09:33 AM

You can also get heat shielded insulation aka hood liner from NAPA, McMaster-Carr, etc. for under the hood.

I've noticed a small decrease in noise when I wrapped my exhaust manifold in fiberglass.

Another option would be to swap covers from a Lexus, if they fit. I know the 90's camry guys like to grab lexus engine covers form the junkyard.

If it's wind noise, adding "vortex generators" aka bumps to the sides of the mirrors can help. They're on most new cars for wind reduction.

A road less traveled would be to try your hand at intake resonators. Glue a dead-end tube to the air intake hose between the filter and throttle body. this modification will take lots of experimenting though

catmandoo62 · #7 03-13-2013, 09:41 AM

dynamat is super spendy.go to the lumber yard and get a roll of frostguard.same stuff but 1/3 the price.it's basically rubberized feltpaper for under shingles on shallow pitched roofs to keep water from backing up under the shingles in winter.or my focus was kinda loud.and the kid wrecked the sdl or better yet i should say a deer did.but anyway it took out the hood.i took the hood pad off the sdl hood and cut it to fit in the focus and it helped alot.

MTI · #8 03-13-2013, 10:59 AM

The Mercedes method of noise encapsulation in some of the diesel models was to have plastic walls closer to the engine, the hood pad and an longer plastic cover for under the engine bay.

Mölyapina · #9 03-13-2013, 04:03 PM

Quote:

Originally Posted by E150GT

Id be interested to see how well you can insulate the car. And for what cost. Ive only driven two toyotas, a 2012 yaris and a 2005 corolla. Theyre both pretty loud. the yaris engine is surprisingly noisy.

So the Yaris is louder than the Corolla? Wow!

Quote:

Originally Posted by SwampYankee

I'd go with Dynamat or similar like DieselPaul said. Inside the cabin under the carpet. Is it direct engine noise or is it resonance?

How would I tell whether it's direct noise or resonance??

Quote:

Originally Posted by catmandoo62

dynamat is super spendy.go to the lumber yard and get a roll of frostguard.same stuff but 1/3 the price.it's basically rubberized feltpaper for under shingles on shallow pitched roofs to keep water from backing up under the shingles in winter.or my focus was kinda loud.and the kid wrecked the sdl or better yet i should say a deer did.but anyway it took out the hood.i took the hood pad off the sdl hood and cut it to fit in the focus and it helped alot.

Have you ever installed Frostguard in a car to tamp down noise? Has anyone else ever done this? How does it work?

Zulfiqar · #10 03-13-2013, 04:13 PM

I have a co-worker who ordered a bunch of heat resistant insulation from mcmaster carr, his 05 corollas odo stopped at 400,000/- the guy simply added this insulation to the firewall and engine room area - even on the hood, it looks like a generator engine room now - all shiny etc.

the other bit that makes the corolla super noisy is the wheel wells - all 4 of them are in the cabin, insulate them with heavy suppressor.

The doors also resonate at high speed, you would need to check the vapor barriers and even apply some thin foam on it too.

btw - the engine mounts also cause a lot of noise to be transmitted to the cab. along with the front subframe mountings.

Mölyapina · #11 03-13-2013, 04:49 PM

Here's what Home Depot has -- it's called GAF StomGuard. It's one inch thick, and I can get 200 square feet for $98.

link · #12 03-13-2013, 04:57 PM

See this: http://www.youtube.com/watch?v=I5E9mjI3y1E and then sell the car to someone who lives far from your home and then you won’t have to listen to it anymore.

Mölyapina · #13 03-13-2013, 05:04 PM

Quote:

Originally Posted by Zulfiqar

I have a co-worker who ordered a bunch of heat resistant insulation from mcmaster carr, his 05 corollas odo stopped at 400,000/- the guy simply added this insulation to the firewall and engine room area - even on the hood, it looks like a generator engine room now - all shiny etc.

the other bit that makes the corolla super noisy is the wheel wells - all 4 of them are in the cabin, insulate them with heavy suppressor.

The doors also resonate at high speed, you would need to check the vapor barriers and even apply some thin foam on it too.

btw - the engine mounts also cause a lot of noise to be transmitted to the cab. along with the front subframe mountings.

Thanks for the information. I just Googled McMaster-Carr.

How do you define "high speed"? We rarely go over 70...

If the engine mounts/subframe bushings were the main culprits, would we feel vibration along with the noise? The car really doesn't vibrate at all below ~3500 RPM..

Volker · #14 03-13-2013, 06:22 PM

Are you sure it is not something broken? Sometimes something like an exhaust heatshield gets loose and resonates at a particular engine RPM giving you some kind of buzz.

Mölyapina · #15 03-13-2013, 06:38 PM

Quote:

Originally Posted by Volker

Are you sure it is not something broken? Sometimes something like an exhaust heatshield gets loose and resonates at a particular engine RPM giving you some kind of buzz.

The car has always been on the louder side (we bought it new). There is a small exhaust leak at the muffler, but that came about because of a car accident that bumped the muffler less than 1000 miles ago (it has 141,000), and it's not significantly louder as a result (you can hear a different exhaust note in the backseat, but it's not any louder, just different).