Power output at high revs

[Raulpereg]

Dear Maserati colleagues,

I've been searching some information about this but was not able to find a concrete answer to my issue so decided to create a new thread. First of all just to mention I own GS as there could be some small differences with the 4200. The thing is that it revs usually with strong feeling of power until 6000 rpm (approx), from that point the engine continue to rev but I don't feel almost any acceleration. I suppose that if theoretic max power is at 7000 rpm I should feel strong acceleration still until that point, but that's not the case. How are your cars performing at high revs? Im mainly talking about 2nd and 3rd gear that is where you really can push to that level in a mountain road. Never tried in 6th

I have found some possible issues at the forum, but none seems to match my problem. It seems that MAF could be an option, but I have tried to drive with the sensor unplugged and didn't feel any big difference. Also I read that those having MAF damaged cannot rev over 5500, and mine revs, but without any acceleration. Another possibility could be the throttle body? But people usually reports here unstable idle more than not being able to open to max...

Could be also an issue with the output through some point of the exhaust?

So just wanted to check you mainly how your cars breathe at high revs.

Thanks in advance for your answers, always learning a lot from you!

Br

 

[Swedish Paul]

Mine keeps powering on/accelerating until the rev limit. I know this doesn’t help much, but I assume mine is normal.

 

[philw696]

Have you plugged a scanner in to see if any codes logged.
It will have the MAF sensor in there now but it will be interesting to as what else is there.

 

[Raulpereg]

Mine keeps powering on/accelerating until the rev limit. I know this doesn’t help much, but I assume mine is normal.

It helps. Now Im sure I have an issue

 

[Raulpereg]

Have you plugged a scanner in to see if any codes logged.
It will have the MAF sensor in there now but it will be interesting to as what else is there.

Just about one year ago but just giving an issue with secondary air that veas fixed... Now is at Maserati and they will run some checks, but just wanted to know how others perform

 

[Raulpereg]

Just an update in case someone is having same issue in future. It seems the issue has been localised. I changed recently one of the primary cats as it was destroyed, but we didn't realised that the secondary cats were seriously blocked. This justifies not just that the engine was not able to work properly at high revs but also why it was overheating when pushed hard. I talked yesterday with Maserati and they are 95% sure this is the issue. They started the car exhaust free from primary cats down and it revs like a turbine now (sounding also like a Harrier ) The secondary cats have been sent to be cleaned to same guys doing the primary one I just replaced. I think the car will be ready next week so I will send an update to confirm if this is really solved.

 

[Zep]

That’s great news. Sounds like you have dodged a bullet on the bits of cat making their way back into the engine.

 

[TimR]

Best way to 'unblock' your secondaries is to remove the cat bits !!!

 

[Raulpereg]

Hi gents. I just picked up my GS yesterday after cleaning the secondary cats and wanted to give an update. Just a quick drive as cannot wait to check the changes, but OH MY GOD. I'm still in shock! This is a complete different car! I always thought that it was no working as it should and now I have the confirmation. It pulls like a beast to the limit and the sound is completely different. I have Larinis installed by previous owner, so don't know how it sounds std. Every time I release the gas it pops with a gutural (don't know if this exists in English ) sound, but the reductions in sport mode are in another galaxy, something absolutely furious! Sport mode is now completely uncivilized to be used in city. Finally I understand what is this car about. Just waiting to Sunday to take a longer ride!