350 tbi injectors suddenly louder ?

[shane colvin]

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Brand new throttle body put on about a year ago, checked all vac lines, map sensor,pvc, new 02 sensor. Sounds like extra air coming from somewhere. Suddenly louder than it normally is. Someone please help,

 

[evilunclegrimace]

The injectors can not suck extra air. The noise that you are hearing is the air that is being pulled through the throttle body. It is normal. You need to find out why the truck is stalling unless you shut it off for the video. Hook the truck to a scanner and find out what the data stream is showing and THEN we can offer some constructive advice.

 

[shane colvin]

The injectors can not suck extra air. The noise that you are hearing is the air that is being pulled through the throttle body. It is normal. You need to find out why the truck is stalling unless you shut it off for the video. Hook the truck to a scanner and find out what the data stream is showing and THEN we can offer some constructive advice.

Just suddenly got louder than normal the other morning,i turned it off in the video just to show the noise. I’ll have to get a scanner and post the data stream as soon as I can. Was thinking it could possibly be the fuel regulator or something. i Still have a lot to learn that’s why I hopped on this forum,

 

[PlayingWithTBI]

I can't tell from your video but the IAC (Idle Air Control) can cause a hissing noise when it's open. Maybe it's trying to compensate for another issue by opening up more than normal? As my favorite Evil Uncle said, get a scanner and look at the data stream.

Edit: I changed the acronym for IAC to Idle Air Control - don't know why I put Intake originally - duh!

 

[Busted Knuckle]

Look for vacuum leaks. Especially the back hose that feeds the MAP sensor. Check the torque on the TBI mounting bolts. These do eat TBI to manifold gaskets. You'll need one every 50,000 miles. The best gaskets have metal in them and are from Mahale, G31133,
on sale for 0.84 : https://www.rockauto.com/en/catalog...,1302264,fuel+&+air,throttle+body+gasket,6474

 

[someotherguy]

I can't tell from your video but the IAC (Intake Air Control) can cause a hissing noise when it's open. Maybe it's trying to compensate for another issue by opening up more than normal? As my favorite Evil Uncle said, get a scanner and look at the data stream.

This, and often the result of the CTS going bad and reading too "cold" causing too rich of mixture, engine begins to bog down so the PCM opens up the IAC trying to keep the idle speed correct.

Richard