Hissing sound can for sure lead you close to an air leak

 

If your fuel trim goes away under revs then it’s likely vacuum leak

if your break booster goes bad it can leak air Inside so try taking the hose off the manifold to be sure and plugging the port with duck tape method

 

This is your throttle body this is actually what was leaking on my truck try spraying break clean in there as deep as you can and see if that does anything

 

I duck tape with brake booster. and do throttle body with break clean. Is the break booster supposed to make niose? When i put my ear next to it i hear stuff.

 

What do you hear?

 

kinda sounds like a winding noise

 

I’m not sure I don’t believe mine did that how are your short term fuel trims looking with the break booster duck tape method

 

do i need to take the hose off the engine? or the brake booster?

 

Take it off the engine and duck tape the open hole on the engine, start the engine and check your fuel trims short and long and just see what they do for a couple mins

 

The clamp is way too tight. i cant get it off

 

If you know the hose is good you can take it off the brake booster but you still have to put duck tape on the end of the hose where it plugs into the break booster

 

******* hoses are tight. I give up

 

i dont think there is leaks. But for some odd reason my check fuel cap light has gone off????

 

You could have a bad gas cap if you already tightened it

when you say you hear a whining noise from your booster it sounds like it could be leaking air

 

The diaphragm can leak air causing pirate air getting to your engine that isn’t measured by your mass air flow sensor. The diaphragm is inside the booster housing so you can spray break clean wherever you want but it won’t show sign of leak. I think you should trust ur gut if you hear a hissing or whine on the driver side especially considering that’s where the booster is located

 

it doesnt sound like air, rather sounds like internal components working with a whining noise

 

Well if you pulled the evap hose already and it didn’t change your short term fuel trims then I don’t think the gas cap is related to your lean codes. Unless you were only looking at long term trim when you pulled that hose

 

But at the very least i would recommend trying to pull the hose off the booster tomorrow it’s just a barbed fitting on that check valve and plug up the hose and check your short term trims because a leaking booster would for sure give you a vacuum leak

 

I was looking at long term only when i pulled that hose. im out of ideas. I might just opt in to pay the 70$ for someone to find it even though im broke

 

I imagine you have fatigued yourself

you can pay someone to find the problem

if I were you before I took it to someone I would recheck the evap hose and watch my short term trim and I would also check the break booster and watch short term trim. And if you haven’t sprayed break clean on the throttle body with engine running where I circled on that pic I would try that too.

id probly try all that after a good night sleep

 

I have fatigued myself for weeks. I've been on multiple forums and get the same ****. I just want my truck to be not lean so i can feel comfortable that my truck is drivable. You have done better than everyone else with the details though.

 

I appreciate that I’ll try to be as specific as possible



This is what’s called a barbed fitting it makes putting the hose on easy but more difficult to take off. This is what the break booster fitting is, that’s why it’s so hard to take the hose off the break booster. You just have to pull hard enough to get it off but not break the fitting on the booster

 

What makes it worse is the clamp on the damn hose too

 

I understand your frustration I was having the same problem and learned a lot in the process and I’d like to see if we can’t help you save some pocket money

 

You have pliers?