egr valve gas mileage

[joshkbomb]

I have a friend who removed the egr valve (he blocked the opening) off his buick and his gas mileage went way up. Would doing that help my Blazer(87 with 350)?

 

[4X4HIGH]

Something else happened at the same time. Blocking the EGR valve will not make the fuel mileage go up.

 

[454k30]

I agree this shouldn't help the mileage. Usually that is only removed and blocked to keep sooty exaust fumes out of the intake.

 

[Dabba]

Forgive me for sounding like a n00b that i am, but why would you want to recycle the exhaust back into the intake mani?

 

[lectric80]

Forgive me for sounding like a n00b that i am, but why would you want to recycle the exhaust back into the intake mani?

By recycling a small amount of the exhaust it helps produce a cleaner exhaust emission. All modern engines recycle a small amount of the exhaust gases to help with emissions.

 

[Dabba]

This must kill the engine/performance no? andddd for i guess replacing the stock exhuast mani with headers would render this system inoperable?

 

[sled_dog]

This must kill the engine/performance no? andddd for i guess replacing the stock exhuast mani with headers would render this system inoperable?

Kill performance? No. Hurt? Yes. But the EGR is only functional at low throttle positions. Wide open throttle it is inactive and not hurting performance at all.

Headers have no effect on an EGR operation unless it is a Vortec engine(96+). The passages for the EGR are integral to the cylinder head, nothing to do with the manifolds.

Inert exhast gases routed back into the cylinders lower combustion temperatures, thus lowering nOX emissions(the nastiest of emissions). It can also IMPROVE fuel mileage, in a properly working system. If there is inert gas in the cylinder, there is less fuel in there. This means slight decreased performance, but also slightly increased economy.

Your friend had something wrong with his EGR system. Most likely a stuck valve.

 

[vortec]

Your friend had something wrong with his EGR system. Most likely a stuck valve.

x2. that's the only logical way that removing it would make much difference in mileage.

 

[Dabba]

Just curious, thanks. My problem was i have no emssions stuff left on the engine at all, i got someone to pass me, so ill just say screw it, haha.

 

[joshkbomb]

I had the valve replaced with a brand new one a couple years ago (bad one caused dying in stop and go traffic) and the truck runs good now, so I guess I'll just leave it alone.
As for my friend, I don't know the mpg numbers he was getting but I don't think his mileage was bad.
I was just curious about it.