Granturismo Sport Cold start Knock/Rattle

[Maseratlee]

I recently purchased my 2014 gts that had been sitting unused for approx 7mnths. The day after I took ownership I noticed a loud mechanical noise on cold starting, for those that are also experiencing this noise I'd appreciate any feedback if any.

Despite searching various topics and forums I've not managed to find any answers or diagnosis for the problem so this thread may be of use to others in the future.

On cold start the engine produces a very loud mechanical rattle/knocking sound coming from the back of the engine, after around 5mins or so when the Oil warms up and comes off cold start the sound goes away.

The car has been with AV Engineering for over a week having various tests done.
Aldous himself hasn't heard this sound before, after testing with various sound equipment he managed to pinpoint it toward the back of the R/H crankcase.

Before moving any further he sent some engine oil away for analysis to ensure no Internal damage had been done to the engine.
Analysis came back, no signs of excessive forgien material, all measured values are within tolerances.
This is good news as it would suggest that there is no internal wear occuring. AV have ordered a sump gasket and will be exploring the pickup/sump area for any potential issues. Although the oil has been recently replaced and is the correct specification they will replace the oil with Shell Helix Ultra 5w40.
That's it for now, I'll keep the thread updated when I hear more.

TIA

 

[Zep]

Glad no wear metal was found, this is very good news. Fingers crossed for better going forward.

 

[midlifecrisis]

It's not a bad idea to send an oil sample away and it relatively cheap to do. From £40 to £60, they'll inform you of wear metals, viscosity and water content. Particularly useful if you have a GT or later QP with the 2 year service regime.

 

[Bebs]

It’s a right f@cker when you can’t pin point issues like that.. very frustrating, especially as it’s a recent purchase and one wants to know if it could be serious.
You are in good hands with Aldous and hopefully you can recoup any diagnosis bills from the vendor.
Keep us posted and best wishes for a positive outcome.

 

[midlifecrisis]

Air con pump?

 

[Sam McGoo]

Not the best start to ownership! But as has been said, couldn't be in better hands as far as these engines are concerned.

 

[schell70]

Given that it only happens when on cold start could it be the secondary air pump? Although I'm not sure they run for as long as 5mins

 

[CatmanV2]

Given that AV is on it, I am keeping quiet!

C

 

[mowlas]

Air con pump?

I have the famous air con rattle at the moment. My sound is a little more hollow and pronounced but not dissimilar. It maybe that you have an early stage version of the rattle.

However if it were the AC pump, I would have expected sound tests to have isolated it as such.

 

[Zep]

Given that AV is on it, I am keeping quiet!

C

I think this is a good plan. If AV have put Ed’s box of microphones on it, they would have found the more obvious culprits.

 

[philw696]

Good Luck for a successful outcome.

 

[Maseratlee]

It’s a right f@cker when you can’t pin point issues like that.. very frustrating, especially as it’s a recent purchase and one wants to know if it could be serious.
You are in good hands with Aldous and hopefully you can recoup any diagnosis bills from the vendor.
Keep us posted and best wishes for a positive outcome.

I bought the car from Performance Paddock In Kent, they've been fantastic from the start, covering the cost of repairs needed including anything else that Aldous finds.

 

[Maseratlee]

Given that it only happens when on cold start could it be the secondary air pump? Although I'm not sure they run for as long as 5mins

That's was the first initial thought, they haven't ruled it out, so they'll probably look at that depending on the outcome of the oil pump/pickup etc

 

[Maseratlee]

I have the famous air con rattle at the moment. My sound is a little more hollow and pronounced but not dissimilar. It maybe that you have an early stage version of the rattle.

However if it were the AC pump, I would have expected sound tests to have isolated it as such.

Me too, does the AC pump make the noise when the engine is warm/off cold starting?

 

[conaero]

My first thought was the ac pump but Voicey would have checked that first, very common. It’s going to be one of those odd ones.

 

[mowlas]

Me too, does the AC pump make the noise when the engine is warm/off cold starting?

In my case it comes on and off regardless of temperature and will continue on any length of journey. Seems to be less when I switch the air con on. Oddly enough, I can hear it more through the cabin than I can from the outside - but that’s probably due to external noise deadening.

 

[Jamin]

You are clearly the chosen one having AV investigate, he's politely declined working on my car twice now as he is in great demand with Rari.
Hope it is something simple. Good luck

 

[Maseratlee]

In my case it comes on and off regardless of temperature and will continue on any length of journey. Seems to be less when I switch the air con on. Oddly enough, I can hear it more through the cabin than I can from the outside - but that’s probably due to external noise deadening.

That's the odd thing, you can't hear this in the cabin.

 

[Maseratlee]

You are clearly the chosen one having AV investigate, he's politely declined working on my car twice now as he is in great demand with Rari.
Hope it is something simple. Good luck

Not sure about that fella, Perfomance paddock have been using AV for over a decade, so that's probably the only reason why they're looking at it, if anything they may even learn something new.

 

[GeoffCapes]

Not sure about that fella, Perfomance paddock have been using AV for over a decade, so that's probably the only reason why they're looking at it, if anything they may even learn something new.

Voicey has not had his workshop for over a decade (5-6 years I think), so I'm not sure that's true. They've probably been using him from the off though as the man knows his stuff.