Hi to all,
I've just imported a 2001 MR2 but can't register it as the noise level is too high. The VOSA test (45 degrees to exhaust and 500mm away) reads 97dB. I bought a sound meter to confirm and it reads the same!
The reading should be 89 and 91 being the max permitted.
I've replaced the genuine exhaust for another genuine one.
Took it to a Toyota dealer who said the noise was coming from the manifold. There are no leaks. They said that some had problems in the early days.
So, the question is: has anyone had the same and got a solution?
regards
Mick
what air filter do you have fitted?
most noise comes from induction kits
and welcome to the club!! s:D :D s:D
standard air filter
Dealer says its a standard exhaust manifold but could use a pic to compare!
thanks
Mick
Gutted precats?
Check Slacey's post about sound levels in the General area.
don't have a piccy of that but i'm sure if you do a search the you'll find one, possible as well that the pre-cats have been removed, plenty of info on that if you do a search
If you take a look at my chart you will see that a precat-gutted car is indeed rather loud, so it could be that. The best way to check is to search for the precat info here, then pull the O2 sensors out and see if they are there or not.
97dB is much louder than 91dB. A 6dB difference is 4 times as loud (every 3dB more is twice as loud). I find it hard to believe that a gutted manifold is any louder than a TRD header (same design as standard header, except no bulges for precats). Could the sound reverberate that much inside gutted chambers? I just don't think so. I'd double-check all of the manifold mounting hardware, including the two bolts/nuts underneath/behind the manifold on the rear of the engine block... could be vibrating.
http://www.spyderchat.com/phpBB/viewtopic.php?t=20736&highlight=
In case it is gutted and that's the problem.
My precats are gutted and it has a Magnex twin exhaust and I really don't think its that loud at all. Presumaby the test is done at high RPM? If so, then it might be a bit too noisy if the precat chamber causes resonance.
I've not been at the back of my own car at high revs. s:? :? s:?
Did you get to the bottom of it, Mick?
Took the car to a main dealer and we both agree that it seems to be an inlet manifold reasonance. The air filter, box and pipes seem normal.
This happened to someone on Spyderchat, too. He went nuts trying to isolate a loud noise that only happened in a certain RPM range and finally determined it was the intake manifold. I'd say take it all apart and put it back together again. Good luck.
Yes Beanie, I agree.
The ESVA test is done at 75% of the engines max RPM from the model report ie 4800rpm. Also it seems noisy whilst driving. I'm going to take the inlet manifold off and have a good look.
Mick
Yep, next week I'll spend a day to strip down the inlet manifold. I'll keep you posted.
Mick
Well, I spent a day poking around and still can't fathom the noise out.
Driving the car the noise definately sounds induction, like if you had taken the air filter off an old carb. car. Revving on the drive it was more a diesel type sound.
I've cleaned the mass flow meter and reset the ECU. Ran slightly better. Checked for rattles from heatshields. Removing the lamda sensors show the pre CATs OK.
The car drives well with plenty of torque in 5th. All the dealer would say was they think it's an induction problem but didn't have a solution!!