4.7 GTS exhaust burble and pops - reduced

[Ryandoc]

Folks

Short timeline for you as follows

1) My exhaust valves playing up, not closing, no big deal always In sport mode
2) Car gets serviced at Maserati, they free them up and they do work for a very short period.
3) Following service end of July, I loose my exhaust burble and overrun pops. It's still great but the cackle on gear change and lifting off throttle is now very civilised, and only really happens lower gears.
4) Last week my indi changes the vacuum solenoid. The sport / non-sport mode now works beautifully so it's all A1 as far as the exhaust valves go. They also endoscoped the exhausts and confirmed they are both fully open. Also naturally you can hear the big change

I can't remember the exact timeline of when things changed in that it's not as boomy and the glorious pops and cackles are probably 25% of what they use to be but they most definitely are massively different.

As we know it's just unburnt fuel igniting in the exhaust. Car is running perfectly so what on earth is going on here. My indi suggested lower octane fuel, sounds plausible. I basically run my car on V-power but did drive around the highlands a few weeks back and did use normal fuel. I happen to know a bit about these fuels, it does no harm whatsoever using normal, but I can buy into the notion that the overrun may be reduced on lower octane.
I currently have a full tank of v-power and have driven 2 hours today, no change. Tonight I've done a battery re-set for an hour, no change.

Short of the car now running differently I'm at a loss. I've gone throw through getting the valves working 100% as I wanted to rule out anything with them such as perhaps not fully opening and strangely enough giving me a better sound due to a distrubed exhaust flow around what is a bluff body and causing swirl etc

Then I saw some of these links online

http://www.maseratilife.com/forums/...aust-sound-issue.html#/topics/18102?_k=qjgisg

Post number 6 on this one !
http://www.ghibliforum.com/forum/ma...-boom-sound-gone.html#/topics/15921?_k=qjgisg

I've just emailed Maserati garage who did my service to ask was my car updated without my knowledge.

Pretty certain it won't have been but short of the lower octane thing being correct (and hopefully it'll rectify it tomorrow when I drive 300 miles) or Maserati have updated my car and toned everything down, I'm at a complete loss and slightly annoyed

My indi also confirmed both my cats were running at correct temperature.

Anyone else lost that loving feeling on their exhaust sounds with a standard set up ??

It's really starting to annoy me that I can't figure out what it is

Cheers

 

[Contigo]

Simple, get an X pipe or H made for it and enjoy more pops.

 

[CatmanV2]

Octane has utterly no bearing on this. The update might have though if there is such a thing. (I tread with caution, it seems that dealers have a habit if either being ill-informed, or simply telling the customers what they want to hear)

Voicey might well be able to tell you what the version of your software is.

C

 

[CatmanV2]

Simple, get an X pipe or H made for it and enjoy more pops.

Almost certainly true

C

 

[Ryandoc]

Almost certainly true

C

If it was a mod that worked definitely, although I'd like to hear it first. However something has changed and I want o get to the bottom of it as it was glorious and perfect before this happened.

 

[Ryandoc]

Octane has utterly no bearing on this. The update might have though if there is such a thing. (I tread with caution, it seems that dealers have a habit if either being ill-informed, or simply telling the customers what they want to hear)

Voicey might well be able to tell you what the version of your software is.

C

Is voicey gemmed up on the software versions etc and is there a way I can see what version I'm on without the comm's gear ?

 

[CatmanV2]

If it was a mod that worked definitely, although I'd like to hear it first. However something has changed and I want o get to the bottom of it as it was glorious and perfect before this happened.

Yes I can totally understand your point

C

 

[CatmanV2]

Is voicey gemmed up on the software versions etc and is there a way I can see what version I'm on without the comm's gear ?

I expect yes and no in that order.

C

 

[BennyD]

Mine pops and bangs with gusto and, if you play with the throttle, you can make it pop and bang as long as you like. I appreciate it's probably costing me 5mpg, but who gives a sh!t? My nagger, certainly not as she says she will divorce me if I tone it down. Happy days?

 

[beau]

Iv used asda/tesco 95 and v power, noticed no difference in exhaust popish/banging at all, currently it's got tesco 95 in and loads of pops/bangs so no idea why yours isn't, but won't be fuel

 

[Ryandoc]

So what would cause this can only be a handful of things, engine running I correctly, lambda sensors out causing incorrect fueling. Knackered silencers or cats.

The valves are fully open so what the **** is going on ??)

 

[Contigo]

If it was a mod that worked definitely, although I'd like to hear it first. However something has changed and I want o get to the bottom of it as it was glorious and perfect before this happened.

No word of a lie, mine used to pop and bang on downchange at 4k rpm like a gunshot. Since having a new clutch it doesn't do it as much maybe that's because changes are quicker and smoother. Again all different characteristics of cars which can change. I wouldn't dwell on it but I do know for sure that fitting a pipe will definitely add more theatre to the drive.

 

[ChrisQP09]

No word of a lie, mine used to pop and bang on downchange at 4k rpm like a gunshot. Since having a new clutch it doesn't do it as much maybe that's because changes are quicker and smoother. Again all different characteristics of cars which can change. I wouldn't dwell on it but I do know for sure that fitting a pipe will definitely add more theatre to the drive.

Seems logical mate if the rev matching on the downshift or up is quicker. Clutch might just need to bed in some more or get her up to 4.5k and drop it.

 

[iainw]

Sorry if this is slight thread drift - but I have been driving mine quite sensibly as I am reticent to let the rev count get too high.
Can you do any damage by having it in high revs a lot of the time - or doing downshifts at say 4,500-5,000 revs?

 

[Contigo]

No! It's a race engine, I downshift at 6k rpm on track with no issues. If the engine speed is too high for a downshift it won't go down to preserve the engine

 

[CatmanV2]

No! It's a race engine, I downshift at 6k rpm on track with no issues. If the engine speed is too high for a downshift it won't go down to preserve the engine

WHS!
Over and over and over again!

C

 

[CatmanV2]

So what would cause this can only be a handful of things, engine running I correctly, lambda sensors out causing incorrect fueling. Knackered silencers or cats.

The valves are fully open so what the **** is going on ??)

I guess there could be a fuel overrun reduction by (perhaps) an injector changing its behaviour. The fuel trims *might* tell. They'd certainly tell you if the Lamdas were heading south, but it's not likely.
Cats possibly I guess

But *personally* I don't think I'd be over worried at this point, unless it's only that you really want more noise. (In that case get an unsilenced X or H) If you *are* worried, get a full diagnostic read and see if there is anything worth worrying about.

C

 

[iainw]

Thanks - thats what I thought/ hoped.
I haven't driven something like this before regularly.
Cue now a driving ban and ASBO from local residents...

 

[Ryandoc]

It's that something has changed very noticeably and why I can't figure out that's bugging me and I preferred the old noise.

Iain not at all just go for it, the gear changes are sicker further up the Rev range anyway and it's not daily track driving on the road so give it the beans and enjoy !

 

[iainw]

I can empathise with you re: the sound change. I would be upset if it changed and I didn't know why. I hope you get it sorted.
I can definitely recommend the X Pipe.
I would really like to do some other exhaust mods but I can't work out what the next, cost effective step would be that would definitely improve the sound.