96 3.4 making sucking sound

My 96 3.4 makes a sucking sound only when I throttle up under load. It sound like heavy intake. I just replaced the intake tube there is no vacume leaks that i can see. Its also running poorly,no powed crappy gas mileage. Would a bad egr valve cause this problem? please help

 

My truck also growls when its opened up under load. Its probably nothing to be worried about. The rough running could be spark plugs, injectors, fuel filter/pump.

 

I suspect a partially plugged cat.

 

Do we have EGR valves??

 

Should be able to isolate it pretty quickly by idling it in your driveway and turning the throttle body by hand and listening. It sounds to me like a loose vacuum hose though - there should be a routing diagram on the underside of the hood that would be good to reference while chasing them all down.

 

I’m going with vacuum leak. The age of the truck makes me wonder if the lines have ever been changed. Get a test gauge.

 

X3, you have a vacuum leak somewhere