I have had this van for about 7 months & have had this problem for the last 6. When you first start driving, the engine sounds real loud- like a jet or a diesel engine. If I stomp on the gas & let it run at high RPM's for a few seconds, the sound goes away & I can feel an increase in power. My first thoughts were the fan clutch had locked up, so I replaced the clutch & it was better for about a week, but came back- no as bad, but still there quite often. This is a thermal clutch- is it common for them to go bad that quick? Is something else causing this problem? The engine is a 4.3 liter V6 VORTEC with about 50,000 miles on it. I have done a fairly extensive tune up recently (with no improvement) including: Oil & filter change, Transmission fluid & filter, Front & rear diff. Lube change, transfer case fluid flush & change, new plugs, dist. Cap, & rotor, air filter, etc. Also I occasionaly get a check engine light for a cylinder misfire- once cylinder 4, & once on cylinder 3- which after clearing go away & the engine never even seemed to misfire. Any help with the noisy fan would be great- it really annoying & I'm sure it's using more gas & robbing me of power.
Wednesday, June 13th, 2007 AT 12:42 AM