About Dave Ward Expertise I`ve been restoring and driving my own 356`s for over 35 years. I`m not a professional mechanic but after all these years can pretty much put a 356 together with my eyes closed. I find there is very little help out there for the 356 hobbiest, so I decided to sign up and share my knowledge. I`ll do my darndest to help out with your questions and if I don`t know the answer, I`ll search as hard as I can to find it for you.
Like I said, I`m not a professional but can certainly relate to your frustrations and problems that sometimes come with restoring one of these little beauties.
Expert: Dave Ward Date: 9/12/2006 Subject: 944 S2 whislting noise
Question Hey Dave,
I have a 1990 944 S2 cab in great condition that has an annoying whistling noise coming from the engine bay. The sound rises and falls with engine revs. It is definitely getting louder and I can't locate the source. Performance hasn't been affected (so far). Any suggestions where to look?
Mark
Answer Hi Mark,
I suppose there are several likely culprits when it comes to odd noises. You'd think for such a beautiful car, Porsche would have dealt with this issue!
Here are three possibilities:
1. Alternator drive belt, or really any belt, if it is a tiny bit loose...the sound should be more pronounced with a cold engine.
2. A whistling could be an air intake issue...perhaps there is a tiny opening at the air inlet, or even along the air path, that is restricted enough to create a whistle.
3. Early water pump failures will sound like a whistle. What's happening is the bearing surface is worn down in such a way as to be loose enough to start whistling. When it squeals, it needs replacing.
Frankly, I'm not sure what you can do when these ideas. Other than wait til the sound gets progressively worse and then identify it. Or, while someone revs the engine slighty, you could use the auto stethoscope kind of tool...lay it on the water pump housing, for example, and the sound...if there is any there...should be amplified in your ears.
