Question about noises
Discussion
When I first had my car, and I lifted off the throttle, there was a strange noise on the overrun which I can only describe as sounding like a large shower of sand. I can't think of any other way of describing it - other than the sound of a large volume of sand pouring out underneath the bonnet. I was going to ask the forum what this could be, but now it's changed. Since my track day, I now get a "rasping" sound from the exhaust on the overrun. It used to do it a little but it has got significantly more noticeable. You know - the nice rasp you get when you lift off as you blip the throttle - a bit like Alfas used to make. It is definitely more noticable now, without a doubt. Don't get me wrong, it's a nice noise - but I am curious as to (a) what exactly makes this sound and (b) why it's got a lot louder since the track day and finally (c) what's the "sand" noise it used to make?
As a mechanical numpty, I'd say it could be exhaust system related. You might have a damaged cat (can't remember if you run one or not) which would give a variety of different sounds if the core was disintegrating or it's blowing. Not much help, but easy(ish)to check/eliminate from possible cause.
Could be that the "sand" noise is still there but is masked by the noisier exhaust, I guess. Meanwhile the exhaust note I'm talking about is similar to the lift-off sound here - you need to hover your mouse over the number 2 in the top left hand box:
Another V8
Remember I'm talking about the rasp as you come off the throttle.
SO it could be that the rasping sound is just the sound that exhaust makes, although I am still curious why it's so much louder now than before the trackday.
As to the "pouring sand" noise..... dunno. Used to hear it a lot on the approach to roundabouts, presumably because (a) road and wind noise were low and (b) engine was on overrun.
Just curious. I like to know what noises are when I hear them. Some of them I can work out - like the odd noise produced when the gear lever was coming loose, but some of them I can't. There's also an odd wailing noise I've heard occasionally, usually accompanied by flashing blue lights (??) but that seems to go away if I accelerate a bit harder.
>> Edited by gregwatson on Monday 27th February 22:05
Another V8
Remember I'm talking about the rasp as you come off the throttle.
SO it could be that the rasping sound is just the sound that exhaust makes, although I am still curious why it's so much louder now than before the trackday.
As to the "pouring sand" noise..... dunno. Used to hear it a lot on the approach to roundabouts, presumably because (a) road and wind noise were low and (b) engine was on overrun.
Just curious. I like to know what noises are when I hear them. Some of them I can work out - like the odd noise produced when the gear lever was coming loose, but some of them I can't. There's also an odd wailing noise I've heard occasionally, usually accompanied by flashing blue lights (??) but that seems to go away if I accelerate a bit harder.
>> Edited by gregwatson on Monday 27th February 22:05
Probably just cleaned out the exhaust a bit, maybe even the cats.
Less muffling happening.
If you check exhaust gas that will tell you if engine is running well. If so then its possibly just exhaust.
If things run ok as before and just the noise has changed I recon its likely to be just the exhaust.
Just guesswork though.
Less muffling happening.
If you check exhaust gas that will tell you if engine is running well. If so then its possibly just exhaust.
If things run ok as before and just the noise has changed I recon its likely to be just the exhaust.
Just guesswork though.
Yeah, perhaps you're right... Just cleared it out a bit perhaps....
Funnily enough in one of my first running reports on the car, I mentioned that the engine / exhaust was far quieter than I was expecting.... And now it's making much more of the right noise.
Wasn't sure if the concept of "cleaning something out" actually had any basis in fact....?
Funnily enough in one of my first running reports on the car, I mentioned that the engine / exhaust was far quieter than I was expecting.... And now it's making much more of the right noise.
Wasn't sure if the concept of "cleaning something out" actually had any basis in fact....?
The Monaro does have quite a loud induction sound that you may just be more attuned to.
It would also be worth checking the air filter. If it is getting clogged the onboard computerised injection will have to put more fuel in the mix so it will run richer and cause more popping (rasping).
I fitted an aftermarket filter which improved the pickup including a small power increase and considering the car only had 28,000 k's on the clock you should have seen the state of the old filter!!!!
It would also be worth checking the air filter. If it is getting clogged the onboard computerised injection will have to put more fuel in the mix so it will run richer and cause more popping (rasping).
I fitted an aftermarket filter which improved the pickup including a small power increase and considering the car only had 28,000 k's on the clock you should have seen the state of the old filter!!!!
PS
Changed my login name for various reasons. One of them being www.b4usearch.com ...
Changed my login name for various reasons. One of them being www.b4usearch.com ...
Edited by zadumbreion on Thursday 29th June 17:52
Edited by zadumbreion on Thursday 29th June 17:52
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