Jump to content

What is this and what does it do?


Recommended Posts

What exactly does this contraption do on my 89 gmc van? (5.7 w/tbi)

 

One lead goes to the airbox, 2 other to the exhaust manifold (one on each side of engine) and a fourth lead at the bottom of the contraption that has a hose, but is not connected to anything. Should it be connected somewhere?

 

Also, the egr valve is just to the left of that (white in color on top w/numbers) and has one lead on it. I took apart my engine to replace the intake manifold gasket, and I am not sure if I reconnected it to the right place. Right now it goes to a little filter next to the "contraption" stated above.

 

Thanks in advance!

 

intake%20001.jpg

Link to comment
Share on other sites

The thing with the black hoses is part of the A.I.R. system...it pumps oxygen into the exhaust to dilute the mixture and also adds O2 to help the cat oxidize the carbon, hydrogen, and nitrogen in the exhaust. The hose that doesn't go anywhere is probably a vent to atmosphere. The item with a fitting on the bottom of it with a pipe going to the exhaust manifold is a check valve. From what I can see in the picture, the EGR appears to be connected correctly.

Link to comment
Share on other sites

The thing with the black hoses is part of the A.I.R. system...it pumps oxygen into the exhaust to dilute the mixture and also adds O2 to help the cat oxidize the carbon, hydrogen, and nitrogen in the exhaust. The hose that doesn't go anywhere is probably a vent to atmosphere. The item with a fitting on the bottom of it with a pipe going to the exhaust manifold is a check valve. From what I can see in the picture, the EGR appears to be connected correctly.

 

 

 

 

Thanks I appreciate the info! From my understanding, the EGR (Exhaust Gas Recirculation) valve takes exhaust gas and puts it into the intake manifold. Where does it get the exhaust gas from if it is not connected to the exhaust?

Link to comment
Share on other sites

I believe (not exactly sure) that there is an extra port in the head, and a similar port on the intake. The EGR gets the exhaust through the port on the head and introduces it into the intake under certain conditions.

Link to comment
Share on other sites

I believe (not exactly sure) that there is an extra port in the head, and a similar port on the intake. The EGR gets the exhaust through the port on the head and introduces it into the intake under certain conditions.

 

 

 

 

That is correct,there are exh. ports in the heads that vent exh. into the intake manifold for the E.G.R. system.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.



×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.