Pontiac G6 Forum banner

1 - 20 of 24 Posts

·
Registered
Joined
·
86 Posts
Discussion Starter #1
Not sure if any of you have dealt with this problem before but my car had been making a hissing/whistling noise for over a year and it had been getting progressively worse. This noise only happened when pressing on the gas and while driving. You could not duplicate the noise if you were in park and pressing on the gas.

I had brought it to the dealership near my home and they heard it but were unable to identify what was causing it. They told me they would ask GM if they had heard of the problem as they could find no bulletins for this problem. I didn't hear back from them and this was quite a few months ago.

Finally unable to stand it any longer and wanting to make sure it would be still covered under warranty I brought my car into the dealership closer to my work where I bought my 6er - this was just a week ago. Not even 30 minutes after I left the car at the dealership I got a call from them telling me I could pick up my car that they believed it had to do with my exhaust and they were ordering it from GM and it would probably take a week to come in. So now within the week they said the exhaust was in and I dropped off my car this morning. By 10:30 they called me to say it was all fixed.

It sounds great...no more whistling and the invoice states " replaced exhaust from flex pipe back ".

The only downside is that they gave me the chrome performance tips - removing my Magnaflow 4" double walled angle cut stainless steel tips because they said they had to put back on the car what was on it when I bought it - but at my request they made sure to give me back my magnaflow tips.

Now I just have to decide if I will have them welded back on or leave it be.

So I hope this helps anyone else that goes through this in case you get a dealership like the first one I dealt with.
 

·
Registered
Joined
·
16 Posts
Anyone know of a Service Bulletin, TSB info regarding this issue I can reference before proceeding with Dealer Service?
 

·
Registered
Joined
·
3 Posts
Keep an eye out on this problem. I had my first exhaust assembly replaced in Oct. 08 at 23K miles. It's now less than 8K miles and 9 months later and the whistle is back. Luckily it is before my 36K for warranty ends. This is a defect in the car and I'm gathering a lot of various email posts to take to the dealer tomorrow because I want this defect warrantied longer.

Perhaps you know this. My tailpipe is very black, I believe it is because the fuel is burning rich and they say that it is supposed to look this way (I've looked at a lot of tail pipes - no, I don't think it should). Considering that is also exhaust based I wonder if there is any connection. Regardless, beware on the longevity of the repair.
 

·
Registered
Joined
·
16 Posts
Great info! Cars at the Dealer now and they knew about the exhaust and replaced. They found some other minor issues they were to finish up today. So I was wondering about the replacement system they installed from their stock. This is a ONE piece system and what makes this one any different than the one they replaced? You’re correct in assuming the black tailpipe is attributed. The Service guy explained this is causing an exhaust restriction. That may be affecting fuel ratio? So I’ll have a discussion with them today and try finding initial cause within the exhaust system and their intentions if/when their replacement one fails and post. Good luck on yours and plz post your results.
 

·
Registered
Joined
·
16 Posts
Got the car back yesterday. They replaced system stating cause was "Resonator".
Service said they have replaced several due to this issue and have not had a return.
So...??? This system should last me till I MOD. This stock unit is "Smothering" this 3.9!
 

·
Registered
Joined
·
3 Posts
Well, as I said, keep an eye out for this issue. My dealer today REFUSED to replace my exaust system again even though I am still under warranty. According to them, GM will not allow them to replace the part "because there is nothing wrong with it." They said that as my exhuast system "settles in" that this is a natural progression of it and that "there is no fix." Okey Dokey...since when does a car company design a car to intentionally develop an obnoxious whistle that does go away when the new part is installed. hmmmm

Now some day, I was told, if GM ever decides that this really is a problem, I'm on the list for a replacement. Sadly, with Pontiac as now the sacrificed group, I'm thinking that GM isn't going to put much effort into Pontiac issues.

I was given the number of GM's customer service to file a complaint and now am awaiting a verdict.

As for the black soot, I was again told that this is a non-issue and that my fuel is running just fine and dandy.
 

·
Registered
Joined
·
16 Posts
Same problem here...

I have the same problem... I'm currently at 78 000KM and my warranty ends at 80 000KM... i got to gm 2 days ago and they told me it was "normal" noise... I hate this noise and i think its getting worse with time... I don't know what to do or to told them... The first guy wasn't hearing it, the second told me its normal...
 

·
LCPL Cobb
Joined
·
67 Posts
The gasket at the flange on my flex pipe went out a couple months ago. I didn't even bother with the dealer. I just used some liquid gasket maker and redid it myself. Haven't had any problems since.
 

·
LCPL Cobb
Joined
·
67 Posts
HAHA! That's funny. nice one.
 

·
Registered
Joined
·
237 Posts
I realize it's an old topic but luckily it came up in a search.

I am now experiencing this wonderful hissing/whistle noise. It only happens going from stop > start up to 1500rpm. As soon as I go over 1500 it stops and it is very faint. Some days a little louder than others but it's never constant.

I have been researching and I heard it could be the tensioner pulley or even PCV valve. I've had a listen and it doesn't sound like the PCV valve or pulley. It sounds more like it's coming from under the engine...

I just got back from the dealer with a very unhappy impression. Here in Canada it is extremely difficult to find a GM dealer that actually makes an attempt to fix your problem. Most of the time if you let them, you will walk out with everything else fixed but the problem and a empty wallet.

Anyway, can anyone suggest what to do? Ask them to replace the exhaust from the flex pipe? This sounds like a huge expensive job. If it's nothing too serious, I might just wait until it gets worse.

Thanks in advance.


Shaun
 

·
Registered
Joined
·
638 Posts
i had the same issues w/ my stock exhaust tha was intermittent, would sometimes wistle but ony when it was cold out. this last fall i put on the GTR exhaust and i love it, if it whistles you cant hear it over the sound of the exhaust LOL
 

·
Registered
Joined
·
16 Posts
Great info! Cars at the Dealer now and they knew about the exhaust and replaced. They found some other minor issues they were to finish up today. So I was wondering about the replacement system they installed from their stock. This is a ONE piece system and what makes this one any different than the one they replaced? You’re correct in assuming the black tailpipe is attributed. The Service guy explained this is causing an exhaust restriction. That may be affecting fuel ratio? So I’ll have a discussion with them today and try finding initial cause within the exhaust system and their intentions if/when their replacement one fails and post. Good luck on yours and plz post your results.
I couldn't agree with you more. My dealer said it's the weep hole in the exhaust and is not covered by GM. I expect to fight with them about this cause I just bought the car and I mentioned the “squeal” before I bought it and they said they would fix it. If it's the weep hole I wonder if enlarging it slightly might stop the whistle or change the pitch. If too big you can probably seal it with JB Weld and re-drill the hole to the stock size. I'd hesitate to seal the hole only because the muffler would fill with water and rot out. But then again, most other mufflers don't have drain holes and last for a long time so how bad could it be?

Art.
 

·
Registered
Joined
·
3 Posts
Hi All - my original post was back in July 2009. I never came back to say that after keeping my car for a week (due to much much much complaining from me) after GM refused to replace my exhause while under warranty, they finally did replace the full exhaust system. After 24,000 miles on the new exhaust - it failed (my original failed right at 24K as well) and the lovely first gear whistle is back and growing louder all the time. Needless to say - if it is going to be fixed now it will be by me and with an after-market exhaust. Then let go of the car - sigh - between that and the crazy creaking that goes on in the front end and the rumbling front breaks, thinking it is time for a change. Good luck all.
 

·
Registered
Joined
·
3 Posts
Just as an FYI, after having this happen on my '07 convertible this winter after 22,000 miles I took it to my regular mechanic (not dealer) who put it up on the lift and verified that the whistle was in the resonator. At his recommendation, I took it to a muffler shop and for about $100 I had the useless resonator replaced with a straight pipe. Works beautifully and unlike an exhaust replacement, in which you expensively replace a badly designed part with a new badly designed part, it can never happen again.
 

·
07 SILVER GT CONVERTIBLE
Joined
·
121 Posts
Hi All - my original post was back in July 2009. I never came back to say that after keeping my car for a week (due to much much much complaining from me) after GM refused to replace my exhause while under warranty, they finally did replace the full exhaust system. After 24,000 miles on the new exhaust - it failed (my original failed right at 24K as well) and the lovely first gear whistle is back and growing louder all the time. Needless to say - if it is going to be fixed now it will be by me and with an after-market exhaust. Then let go of the car - sigh - between that and the crazy creaking that goes on in the front end and the rumbling front breaks, thinking it is time for a change. Good luck all.
I had the same experience replaced once under warranty at 40000 km and it started whistling again at 90000 km decided to go after market GTR sounds gread and guess what NO WHISTLE.That resonator is a pos
 

·
Registered
Joined
·
5 Posts
There is a 'Service Bulletin' for the resonator in the muffler

Just took my 08' G6 with 35K into the dealership today for this exact issue.

I didn't catch the number, but they showed me a July 2010 Service Bulletin for the title said 'Muffler Whistle'

Might or might not get a copy of the report next week when the part arrives.

But the dealer is replacing this item for free.
 
1 - 20 of 24 Posts
Top