exhast noise at around 3000 revs.

[bgarry]

Hi All,
I bought an 2003 Astra SRI a few weeks ago and I've noticed that there quite a lot of what seems to be exhast noise at around 3000 revs.
It's most notceable when accelerating from say 100km-110km in 5th gear and the revs are between 2750-3000. Everything is stock on the car.
Has anyone else had this problem?

Thanks,
Brendan

[blueraven]

i dont really know what you mean by "exhuast noise" (cos..um...they should make noise?) but what i think you mean is a much more pronounced noise...


anyway, how much do you know about tuned resonance? basically, the 'volume' of the exhaust obviously changes as the rpm goes up. manufacturers have to abide by both noise and emmisions regulations, which are tested at certain rpms in different countries, the manufacturer tunes their vehicale as such which can lead to "flat spots"(if they know they will be tested at 3000rpm eg, they will lean out etc to make sure it within emissions at that point) and also sometimes the resonance of the exhaust will change dramatically at certain rpm to change the frequency of the exhaust note to get past noise regulations. your "exhaust noise" is prolly due to the fast that the astra is in reality and VERY quiet car for a turbo, and has possibly tuned the exhuast note to be slightly louder at 3000-ish rpm compared to higher/lower.


but thats just me putting a logical spin on things...my exhuast is custom made, and is very loud when driving..but is somehow almost dead quiet between 2000-3000 when cruising....

[MatsHolden]

Is it a 2.2 SRi or an SRi Turbo?

[bgarry]

Hi and thanks for replying,
The car is a SRI 2.2 and not the Turbo model.
I agree that the car is normally quiet but it the noise I'm getting is a very low frequency drone at around 3000 revs in 5th gear, If you back of off the accelerator the sound goes and if you up the revs then it's quieter.
A similar post was posed by Blue Sri quite a while ago but there was no post to say if or how it was resolved.



Brendan

[V-R]

Mind if i ask how many kms on the car?

My last car (not an Astra) started to resonate more after a certain number ok kms at around 3k rpm due to the heatshield loosening up over time from the exhaust vibration - was easily tightened at each service though.

Not to say this is the problem of course, however I just bought an 03 SRi yesterday so will keep an ear out for this and see if I notice anything on mine.

[bgarry]

About 45,000km on the clock

[Clint]

is it exhaust noise or do you think its exhaut noise?

until a week ago my car sounded like it made a lot of noise from the exhaust between 2 and just over 3000 rpm when accelerating. it was a very loud deep sound. we were looking at the engine for something else and noticed one of the clips on the air box was loose and had unclipped, bent the clip to make it hold tighter, clipped it back on and the noise was gone.

i wish the rest of my exhaust was that easy to fix...

[V-R]

I had a brief drive of my car last night and didn't really notice much exhaust noise...

However, I did notice it was a raspier sound when taking off (while the clutch was sort of engaged) but after that seems to be ok (prob extends to around 3k rpm).

Will monitor it again next time I go for a drive and see if I notice anything.

[oneightoo]

Hi All,
I bought an 2003 Astra SRI a few weeks ago and I've noticed that there quite a lot of what seems to be exhast noise at around 3000 revs.
It's most notceable when accelerating from say 100km-110km in 5th gear and the revs are between 2750-3000. Everything is stock on the car.
Has anyone else had this problem?

Thanks,
Brendan

i had an 03 SRi, and the noice it makes is normal mate.. where you said it makes noise, is where mine made noise when i bought it brand new..

[robdbooth]

I've got the same problem with a 2003 2.2 Astra Elegance Auto. Sounds just like a blowing exhaust but the exhaust is not leaking. There is vibration through the floor with the noise at a few hundred revs either side of around 2,700 revs and its worse under load. Just changed the rear engine mount and it improved, but not by much. Its a very annoying drone - can't believe a new car could have this same problem and not be faulty.