Originally Posted by dumppicker
Help I just picked this car up. I drove it for 2 hours at 75 mph and had no problems with this 3800. After getting home with it I noticed an engine noise when you rev it up. I changed the oil and it made no difference. When the engine is idling you do not tend to hear it. When you increase the rpms from 2000 – 3000 it is very pronounced and sounds like a diesel engine. It appears that the noise is coming from the intake. Oil pressure is about 40 pounds. Please help with some good news. Thanks
Welcome to Bonneville Club! Here are two possibilities. If you are lucky, it could be a bad harmonic balancer (crankshaft pulley) - They are only about $100. The clatter they make can be pretty loud and is usually not as regular in frequency as, say, a rod bearing. But it could also be a rod bearing going out - they do sound like you have described. In that case, you will need to pull the engine and purchase a crank kit for about $200, and then spend another $200 for gaskets and seals. Maybe it'* the HB.