Anyone heard this noise in their 308?

I have a carbed 1979 GT4.
I have had the car for 15 months and in the last couple of days I have noticed a whistling noise from the right side of the engine.Its not always present but it seems to go with the revs.Today I could hear it at idle,othertimes no.It seems to stop at higher speeds and gears!
I would describe it as a high pitched whistling metallic sound.
Bearing noise is generally a lower pitched grating rumbling noise,could it be the belts?
All opinions appreciated.

 

Could be the cam belt tensioner bearings. How old are they? Does it go away as the engine warms up? I had a similar sound in my car after I bought it but replaced the belts and bearings it went away.

 

I think I'm getting the same noise. Mine goes away when it gets good and warm. Any ideas are much appreciated.

 

alternator.

noise changes with temp and load depending on demand and state of battery charge.

just my .02

 

I had what I'm thinking may have been a similar sound from my '87 Mondial--Almost a whistling sound? I would only get it at start up, and it would go away after several minutes of driving.

It appears that it was one of the bearings on the water pump tensioner. Both were replaced and one of the old ones felt quite notchy when tested. The engine no longer makes the sound since their replacement.

I'm not sure if your car is similar, I know at least some of the belt arrangements changed, but perhaps it is. I didn't have it all the time, although I suspect I would have if I'd waited.

Perhaps something to consider?

 

Bill,the cam belts were replaced in 2009,dont know for sure re the tensioners.
Car Reaper,thats interesting,I have had to replace the battery in the last few days(it died I mean really) and the alternator was under investigation as the culprit.
Familycar,there is a way to be sure I think, maybe to release the tension on the A/C,water pump and alternator belts one at a time would eliminate suspects.But that would depend on if the noise was always there???

 

Whatever the cause, better make sure the cam belt tensioners were replaced with the belts!

 

Coming back from Mn. this summer we noticed a similiar noise that would ,at times, disappear. It turned out to be the AC clutch bearing. Never needed AC UP here! st

 

The cam belts were done by the P.O.I will have to track him down.
The good news is that I took the car out for a short and tentative run this morning and apart from two short bursts of whistling while under load that was it! The car ran perfect except when I got her home the fans came on and the idle revs were fluctuating.The new battery may not have enough power.
Methinks carreaper has summed it up as the alternator under load!!!Still I will check out all angles,hope this has been of help to all and sundry!

 

Put a multimeter on the car cold and off, record the voltage.

start car as you would to warm it up for a drive. record the voltage.

while the car is still a bit cold, and at a steady rpm, turn on the headlights.
Listen for the alternator to whine, and record the voltage.

you can also do this with amps using a meter.

your battery cables may be corroded on the inside, which will work the hell out of the alternator also.

good luck, hope this helps narrow the issue.

 

buy a relatively inexpensive automotive stethescope. You can use it with the probe to pinpoint noises, or take off the probe and just use the tube to locate sounds. These tools are invaluable to check for individual bearing noises in a crowded engine compartment.As long as you can duplicate the noise daily, and it lasts longer than a few seconds , you will find it.

 

I guess thats reading between the pos. and neg. battery terminals!!!

 

Good idea will do!

 

Mine makes a squeaky sound on startup in cold weather...I guess it's the external belts, because it goes away after 30 seconds or so of warmup.

The louvered lower rear panel that covers the exhaust system also rattles and buzzes from time to time...need to get down there and check for loose or missing fasteners.

 

I have carried out the tests and with the engine off and cold,12.7 V
cold idling 12.47V
headlights on 12.20V
warm idle 12.98V
warm engine off 12.81V
Is this good or bad news with a new battery?

 

no advice, but i have a 78, and it suddenly started making the same noise a couple of years ago. i solved the problem by having the engine rebuilt.

kidding. i did nothing and the noise seemed not to affect the car.

 

Cheap fix eh!

 

your alternator should put out about 13.7 volts, not to exceed 15 volts. You may have bad diodes in the voltage regulator, or a bad battery that will not take the alternator output.

i would bet the alternator is bad.

you can have it load tested at a Autozone or similar parts store if there is one close.

12.5 is normal for a charged, connected, not in use battery.

 

When you checked for voltage at the batt, did you check to be sure the charge light was OFF? After starting you have to get the RPM up to around 2200 before the alternator will begin charging. After that initial RPM surge to 2200, it will charge at idle. I do not understand why Ferrari set it up that way but they did.

Check the batt voltage at around 2500 RPM. It should be at least 13v but not more than 15.2. Then let the RPM drop to idle and check again. It should be above 12.6V at idle.

 

Not to sound like a broken record but my 85 QV does the whistle as well, off and on and only when cold, could be lots of things, bearings, belt etc, alternator, I would check with a stethescope but that can be tricky, mine has done it off and on for three years with no problems. More annoying than anything but it freaked me out when I first bought the car.

 

Every car guy should have a auto stethoscope, they are essential, and will rule out many noises. You can put one on the belt tensioner nut and water pump housing and rule out both of these within seconds. I have found many weird noises with them and also it is fun listening to all the neat engine sounds. Dont get the tube caught in any belts!

http://www.amazon.com/MECHANICS-STETHOSCOPE-ENGINE-DIAGNOSTIC-AUTO/dp/B002A1IQ58

 

Ditto, and that whistling noise could also be in the muffler which isn't uncommon.

Try blocking off the tailpipes, 1st one side and then the other and see if the sound goes away.

 

I doubt that its the muffler but I will try the revving to 2500 rpm etc. and see what happens!!!

 

Took her out for a 15 minute drive yesterday and read the terminals when I came back.
Engine off 13.08V
Engine revving over 2.5k 13.48V
When revving I could hear the whistle but it stopped before I finished revving.
Thanks for the info,I will bank this thread.
Probably the old battery failing was putting the alternator under more than normal load hence the whistling.New battery may take a while to fully charge also!

 

I do know this, many people have had whistling problems come from their exhaust tips. On some models the screens in there somehow causes a whistling problem, like the belt snapping problem on happens to some. I sill suggest the stethoscope you would be surprised the sounds you can track down. I had a rattling noise I found in my transfer gears. I turned out that it only happened below 800-900 rpms and the cars was supposed to idle at around 1000. I increased the idle and the rattling went away.