Low hum at 80mph
05-29-2003, 10:21 AM
#1
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Location: Iowa
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Low hum at 80mph
A bit after getting new belts on my '91 944S2, I found that when I reach 80mph on the freeway I now hear a very low pitch hum. It seems to be from the passenger front area of the car, starts near 80mph, and only quits when I slow down to around 64mph or push in the clutch. I can push the clutch quickly in and let it out and the hum goes away for maybe four seconds, but then it comes back.
Ideas?
Ideas?
05-29-2003, 12:41 PM
#2
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Sounds a bit like the infamous Oil Pressure Relief Valve, except that most people experience it at lower rpm's.
If this is the problem, it may be an easy fix.I replaced my O-rings on the valve and it solved my problem. Others have replaced the entire valve.
The valve is located under the oil filter - the visible part is about the size of a large coin. (I am being vague, as I do not remember the exact size, but hopefully it is enough info. for you to locate it.)
I had to get the O-rings from the local Porsche dealer as the mail order shop with which I typically do business did not stock the parts.
If this is the problem, it may be an easy fix.I replaced my O-rings on the valve and it solved my problem. Others have replaced the entire valve.
The valve is located under the oil filter - the visible part is about the size of a large coin. (I am being vague, as I do not remember the exact size, but hopefully it is enough info. for you to locate it.)
I had to get the O-rings from the local Porsche dealer as the mail order shop with which I typically do business did not stock the parts.
