Question about the air intake system

Hello,

I was wondering if anyone could help me out with explaining what the flap in the air intake system is for, im not sure how to describe it very well but there is a flap were the plastic like hosing is at inside of it. I tried looking every were online for what it is and what is does etc but having no luck.

My Taho is a 95 v8 4x4 and im just trying to find out what this flap in the air hose or intake how ever you would call it does to prove to this guy aka my dad that is has nothing to do with my truck putting out gas fumes but is instead the fuel regulater as gas is getting the oil, truck is harder to start, gas goes by faster etc and i had this problem before with my old truck and so i know the gas fumes are stronger and getting inside the truck not because of this flap but of the regulater.

My dad put some kinda spring to keep this flap open at all times, and been trying to tell him that its not the problem, but he has it stuck in his mind that is it but im not wanting the thing open at all times cause it shouldnt be like that in the first place.

Any information about this dang flap and what its for etc would be really great.

Thanks,

the fuel fumes may very well be a hole in the fuel regulator diaphram..remove the vacuum line to it ,,,if it has fuel or smells of fuel replace before you damage the engine because fuel will damage the oil in the crankcase...or the TBI has a ruptured diaphram ...which is leaking continuously in the intake manifold..

the flap is a question I really don't get...what do you have for fuel control ...injectors or is this throttle body injection...[looks like a carb]..?


could this be the hot air pipe from the exhaust manifold to aid in heating the air going to the TBI ? this is used to regulate the air temp when it is cold out like below 50deg F.if this is forced open when cold out you may have problems use more fuel...if you do live in AZ. this would not be that often,,,but it does happen to get cold there at times...

Oh, it could be a hole in the regulater im not sure but i do know that the regulater is going bad and has been getting worse over time.

the flap is a question I really don't get...what do you have for fuel control ...injectors or is this throttle body injection...[looks like a carb]..?

I think its fuel injectors, but for the flap like i said its hard for me to explain but i asked my brother who also has a taho but lives in a diffrent state about what it is and he told me it was for the air polution pump but it looks like there is a part the goes from were this flap is to the manifold that is missing. I can take a picture if you think that would help more since i cant describe it right on what it is.

But my dad used some kind of spring to keep it open at all times and i dont really like having it like that, but he dont know what is for either which is why im trying to find out more about it. I had read somewere about a flap in the air intake that opens up when air goes through, like the more air going through the more the flap gets pushed back, but it said somthing about the idleing as well but have no clue if its the same flap or not.

that then is the air pump check valves ...these need replacing...this is used to reduce emissions ..this is a california required setup..my state this is not found...when the air pump pumps air into the exhaust on cold start this helps the cat converter reduce pollutants...

when this check valve is broken exhaust gases get into areas that then cause issues with proper engine operation..this needs replacing.

I dont understand, sorry still learning about all this but are you talking about the part the seems to connect from were this flap is to the manifold that is missing? or are you talking about the flap?

Should i take the spring that my dad had used to keep this flap open at all times? or does it matter at all cause im still not sure what it is for.

On the bottom of the flap, is there a hose to the exhaust manifold? Not sure about your 95 but on my 90 K1500, there is a heat riser to intake for cold operation. After a while the flap does not work anymore and it won't run well when it is hot.

//2000CAYukon

Oh im not to sure, ill check it out reply back about that. I might just take a picture and upload it cause i cant really explain to well about what it is.

All i know is my truck has gotten harder to start during the summer and winter, gas seems to be getting in the oil, there is strong gas fumes getting inside the truck and the spark plugs are looking black, my guess is fuel regulater as i had this problem before on a 94 gmc gimmy.

When it comes down to this flap thats in the air intake my dad though it was casuing a problem with my truck not wanting to start right but after around 20mins i would get it going, but this started after braking down from my truck loseing all power, my dad came to were i broke down at and started messing with fuses and stuff but i knew it was somthing to do with battery connection. The tow truck guy was the one who noticed that a wire was not conenct properly but was like sticking it place. After fixing that is when my truck was not wanting to startup right and thats when my dad got it stuck in his mind its because of this flap, and i knew it wasnt so i got online did some research and found the problem as it was the fuel injector relay fuse cause my dad pull ea realy fuse out and reseated them but didnt put the fule injector relay fuse back in correctly. He still has it stuck in his mind it was this flap and now he has it rigged to be open all the time and im not sure if it should be so thats why im trying to find out what the heck its for.

But there seems to be a peice missing that looks like it goes from the air intake too the manifold, i think thats what j cAT is saying somthing about that part thats missing is air pump check valves.

Ill just take a picture tomorrow and upload it, that may help better in understanding what this part is.

Ill just take a picture tomorrow and upload it, that may help better in understanding what this part is.[/quote]


these pictures will aid in getting you the repair info you need..