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Discussion Starter #1
My car has always had a a slightly audible tapping sound at idle. It went away when the engine warmed up (most of the time). After picking the car up from the dealer for the exhaust manifold/pre-cat replacement, I noticed the tapping is quite loud and ALWAYS present at idle. It goes away completely at over 900 RPM but is down right emabrassing at stop lights (I actually had some guy yell at me "Hey dude, what's wrong with your car?").

Anyway, my car is a MNA buyback. The reason the original owner wanted MNA to buy it back was because of "a lound tapping noise in the engine". Hmmmm. MNA claims they replaced the engine before reselling it to me.

So, it's off to the dealer in the next day or two to see what's wrong. Anyone else heard of this? Possibly a noisy oil pump? It's coming from the driver side of the engine compartment best I can tell.

Buzz
 

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Discussion Starter #3
Mine has it on startup but not after the engine is warm...could be low on oil?
It doesn't show low and the oil pressure is pretty much always pegged out (high). I did notice that the oil pressure does not drop at idle like it used to but that may be because the AC is always on which keeps the RPMs up.

Has anyone looked down into the oil filler with the cap off while the engine is running? Should you see any oil?
 

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Dry sump systems don't always show a pressure drop when they are low...my rossa was 2pts low once and she still sat at 65psi I would recommend checking it.
 

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I'd find an independent Ferrari mechanic and ask him for a listen. All kinds of benign and serious things can tap at idle, it takes a bit of an ear to understand them.
 

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Dry sump systems don't always show a pressure drop when they are low...my rossa was 2pts low once and she still sat at 65psi I would recommend checking it.
That's true and I do remember reading that because of the multiple reservoirs and coolers that the oil does not circulate correctly until at least operating temperature. Mine makes a horrible racquet until it warms up if it's been sitting overnight until the temp. rises.

A weak valve spring or even an exhaust leak could be possiblilties.
 

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i had the same issue, after ruling out the oil issue, local mechanic found the serpintine belt was almost broken, replaced it for $350 and no more problems
 

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Discussion Starter #8
I have been noticing the oil pressure pegged out at 70 all the time even at idle. On the way home today I stopped at a red light and noticed no tapping. I looked down and the oil pressure was at 35 like normal. Stayed like that for a couple of blocks. Next red light it's at 35 then jumps to 70 while idle. No rpm change at all. Tapping is back. It stayed at 70 the rest of the way home.

It's going to PP afer vacation (they're swamped) :(
 

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Question.....

"My car has always had a a slightly audible tapping sound at idle. It went away when the engine warmed up (most of the time). After picking the car up from the dealer for the exhaust manifold/pre-cat replacement, I noticed the tapping is quite loud and ALWAYS present at idle. It goes away completely at over 900 RPM but is down right emabrassing at stop lights (I actually had some guy yell at me "Hey dude, what's wrong with your car?"). "

So you put on new exhaust manifolds and pre-cats... You effectively lowered your back pressure on your engine... I would say you have a bad/burned exhaust valve or valves on one of your cylinders... A leak down test or a quick compression test should show one of the cylinders to have less compression than the others......

Your oil pressure sounds a bit wierd as well.. At idle on a warm engine it should be around 35 pounds, hitting 70 pounds of pressure around 3000 to 4000 rpm and hold that to top end..

Just my guess... Let us know what they say!!!
 

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Tapping along with fluctuating oil pressure is a bad bad thing. Maserati may soon be replacing your engine, if they didn't before.
 

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Discussion Starter #13
The exhaust manifolds and pre-cats were warranty replacements. The pre-cats are an integral part of the manifolds. Everything is stock. No mods.

Ill keep you posted.
 

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Your oil pressure sounds a bit wierd as well.. At idle on a warm engine it should be around 35 pounds, hitting 70 pounds of pressure around 3000 to 4000 rpm and hold that to top end..
mine holds those values now (2.5 > 5 bar though europe) but in its early days when things were tighter it held 5 bar (70lbs) all the time regardless of RPM?
 

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A tapping at idle sounds like a hydraulic lifter problem.

Can you get a mechanics stethoscope, and listen to the engine?
You want to put the tip on each intake and exhaust manifold, next to the cylinder head.

Listen for something that sounds different from all the other cylinders.
 

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I have the same sound on my 2003 GT coupe. It is after the car has been cool for an while. I took it to the dealer (Auto Gallery), they said it was from the fuel injection rail that run on the cam covers. My oil gauge runs at around 35 @ idle and @ 70 when over 15 MPH.
Ron
 

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A tapping at idle sounds like a hydraulic lifter problem.

Can you get a mechanics stethoscope, and listen to the engine?
You want to put the tip on each intake and exhaust manifold, next to the cylinder head.

Listen for something that sounds different from all the other cylinders.

I was going to say that earlier but I believe our engines don't have hydraulic lifters since those are found in push-rod motors. Otherwise I'd swear thats exactly what it is. I had a Ram last year I used a tow vehicle and it had a hyd. lifter that went bad with the same exact symptoms. I replaced that one myself but that's only because I could get the lifter and gaskets pretty easily.
If the noise is sporatic like that it's go to be realted to lube or exhaust heat i.e. a manifold gasket. Injectors can also tap if they are clogging.
 

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my 04 does the same thing

My porsche boxster s did it as well as my friend's F430. I was always told that it was the lifters making the noise if the engine was slightly low on oil. my car is going in for its 6k service soon so I will have them check it out.
 

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I was going to say that earlier but I believe our engines don't have hydraulic lifters since those are found in push-rod motors. Otherwise I'd swear thats exactly what it is. I had a Ram last year I used a tow vehicle and it had a hyd. lifter that went bad with the same exact symptoms. I replaced that one myself but that's only because I could get the lifter and gaskets pretty easily.
If the noise is sporatic like that it's go to be realted to lube or exhaust heat i.e. a manifold gasket. Injectors can also tap if they are clogging.
http://eurospares.co.uk/partTable.asp?M=3&Mo=494&A=1&B=28003&S=

Looking at the diagram, I would assume that they are hydraulic, as there is no indication of it having shims to set the valve clearance.
 

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http://eurospares.co.uk/partTable.asp?M=3&Mo=494&A=1&B=28003&S=

Looking at the diagram, I would assume that they are hydraulic, as there is no indication of it having shims to set the valve clearance.
Looking at the diagram and correct me if I'm wrong, it looks like a shim and bucket at the opposite end of the valve. Our MV engines are basically 4 cylinders out of a Ferrari F1 engine from the early nineties. I was looking at our parts fiches and comparing. I could be way off.

Oh, can you check the vin's to see if it's the original engine? Replaced could have meant that they replaced the engine back into the car after they took it out. Hopefully the original owner was mindful of what oil or additives he put in the car.
 
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