Yea. thats the good ole 4.3.. Well. is it a Blazer or trail blazer.. The whooshing sound you hear may be the fan coming on. My 5.0 did this, very loud, very annoying.. No biggy. But its doesn't effect coolant flow... thats directed by RPM. I dought the motor would rev itself up to cool it down... it makes no sense.. The less friction, the less heat.... You could have an idle air problem.. Have you checked the codes... there could be some stored..
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1994 Taurus SHO MTX
134k 3.0 DOHC 60 degree V6
Intake
plans:Eibach lowering springs (1'' front .5'' rear)
'96 Brake upgrade
KYB GR-2 struts
BBB (big bore butterflier)
Extrude honed intake
3.2 swap with balanced rotating assembly
stage one cams
full custom exhaust
BOOST
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