Alright now I have a weird noise coming from the black hose that goes from the top middle of the intake plenum and goes into the Idle air control valve. The noise sounds like a really loud sucking noise. I thought the hose might have a little vacuum leak so I replaced it and still the same sound and loudness. The sound is coming from inside the hose and now my truck is using twice the fuel, yes I said it Twice the fuel. The truck idles and runs great and no Engine light has come on. Could the idle air control valve be stuck wide open and causing that sound or maybe some dirt or something is caught in the intake plenum. Has anyone ever had this.

 

Have you removed the entire hose assembly from the MAF to the idle control solenoid. Do that then get back to us with what you see.

 

are you talking while its running or what should i be looking for.

 

k i pulled it apart i dont see anything.

 

Now it is getting interesting. Do you have a check engine light on, if so what are the fault code numbers?
Assuming there are no cracks, I am stumped. Also, even if it were cracked and you have no codes, it should not effect your mileage the way you mentioned.

 

Thats the thing no engine codes. and i swear im not messing with you. lol

 

I had lean codes before i redid the top part of motor but no codes since and it seems to burn way more fuel before the rebuild along with that sucking noise.

 

There is a large vac hose to the brake booster. Assure that is on.
Also there is another large black hose on the plenum next the brake hose.
Check that too.

Check that the 6 bolts holding the plenum down are all evenly torqued.

Check for a crack in the black plastic air conduits which go from the MAF to the air box.

Check for the hose clamps on each end of the MAF.

And - hopefully the intake manifold went on just fine with the valley gasket.

Ah, OK I have this figured out..

Your IACV or idle control motor has gone to the extreme OPEN position to compensate for OTHER problems with your motor to keep it running.

Probably a vacuum leak if no codes.

 

I will try to get a smoke test done tomorrow

 

Well problem finally solved. I figured out how to smoke test it myself with a cigar and it worked so well i recommend it to any one. I found 4 vacuum leaks and it still puzzles me why it didn't trip a code. Fixed 3 of 4 leaks but the 4th was a minor leak but would have been the most expensive. Shes is great now. So if Anyone wants to know how to smoke there own vehicle for the cost of a cheap cigar give me a shout. Oh ya that sucking noise has quieted right down now.