Removing emissions......what is this???

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SASKCHEYENNE75

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Can't hurt to check, but if it wasn't stuck open before he disconnected the hose.I can't see how it got opened. Did you by any chance do something like reach under with your fingers and move the valve pintle?
No i didn't touch anything inside...just disconnected the vacuum hose on it and put a slip on vacuum port plug on the egr and also on the other two spots where the egr was connected (port on top of thermostat housing and front of carb)
 

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Do your research on EGR. There is zero benefit in disabling working EGR but several disadvantages. Better MPG, cooler combustion chambers, ability to run more timing. The simplest way I can describe this is at low load conditions a partial charge of exhaust gas( inert) dilutes the fresh air and fuel charge so the re is less oxygen and fuel in the combustion chamber. Less burn means less heat and less fuel consumption.It is inop cold and it is inop on acceleration or under load. So no more power at WOT .

Think of it like this, and these are not actual numbers but numbers to make operation understandable. At cruise speed the EGR valve opens and allows the cylinder to fill 1/2 with exhaust gas 1/2 with air/fuel, so you burn 1/2 as much fuel,step on the gas pedal, the EGR valve closes and now you are burning only air and fuel, power goes up mpg goes down.

I generally disagree with this statement. It is purely an emissions boondoggle in these older trucks and is a potential source for maintenance issues in the future. If your vehicle is running great and has enough power it will indeed help your engine at cruise by effectively making it work like a smaller displacement motor. Most of these old trucks aren’t operated in a way that would take advantage of that benefit at all. My take on it is to wait for something on it to fail and then fix it by completely removing the EGR system. If it is working as intended and the truck is working right, then leave it as-is until it isn’t... which shouldn’t be too long as the EGR system is well known as a point of failure.

When everything is working right it isn’t a big deal except for the carbon buildup from the exhaust in the intake... when it isn’t working right, it will cause all kinds of drivability issues.

As for the issue you are having now, I would check to make sure you didn’t leave any vacuum sources open. You should be able to hear the sucking sound with it running.
 

SASKCHEYENNE75

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I generally disagree with this statement. It is purely an emissions boondoggle in these older trucks and is a potential source for maintenance issues in the future. If your vehicle is running great and has enough power it will indeed help your engine at cruise by effectively making it work like a smaller displacement motor. Most of these old trucks aren’t operated in a way that would take advantage of that benefit at all. My take on it is to wait for something on it to fail and then fix it by completely removing the EGR system. If it is working as intended and the truck is working right, then leave it as-is until it isn’t... which shouldn’t be too long as the EGR system is well known as a point of failure.

When everything is working right it isn’t a big deal except for the carbon buildup from the exhaust in the intake... when it isn’t working right, it will cause all kinds of drivability issues.

As for the issue you are having now, I would check to make sure you didn’t leave any vacuum sources open. You should be able to hear the sucking sound with it running.
Yes absolutely that will be something I check for. As for the EGR I think my frustration is that it ran fine before and now it doesn't because I tinkered with it. I get what you're saying though totally
 

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Yes absolutely that will be something I check for. As for the EGR I think my frustration is that it ran fine before and now it doesn't because I tinkered with it. I get what you're saying though totally

Yeah, I would almost guarantee you left a vacuum leak somewhere. There's something to be said for not messing with something when it is running right.
 

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So I should be getting a block off plate and eliminating it completely therefore no risk of it being stuck.
I would. And check for vac. leaks and bad hoses.
 

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Im starting to think that might be the best option as it ran fine before
Sounds like all that carb spraying and parts removing bit ya.That spraying certainly can but you can use it to check for vac leaks if you do it methodically
 

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I generally disagree with this statement. It is purely an emissions boondoggle in these older trucks and is a potential source for maintenance issues in the future. If your vehicle is running great and has enough power it will indeed help your engine at cruise by effectively making it work like a smaller displacement motor. Most of these old trucks aren’t operated in a way that would take advantage of that benefit at all. My take on it is to wait for something on it to fail and then fix it by completely removing the EGR system. If it is working as intended and the truck is working right, then leave it as-is until it isn’t... which shouldn’t be too long as the EGR system is well known as a point of failure.

When everything is working right it isn’t a big deal except for the carbon buildup from the exhaust in the intake... when it isn’t working right, it will cause all kinds of drivability issues.

As for the issue you are having now, I would check to make sure you didn’t leave any vacuum sources open. You should be able to hear the sucking sound with it running.[/QUOTE

Don't want to start a war. But everyone on the fence regarding EGR Google the following. EGR wiki,,,, EGR and preignition,,, EGR and https://www.motor.com/magazine-summary/driveability-corner-oct-2012/
my 1985 305 c10 runs way better with it.


Don't want to start a war. I was just like many of you, I used to think EGR was useless and just emissions,and needed to be disabled, but years in the business has taught me different, yes even on old trucks. The automotive engineers aren't stupid there's usually a pretty good reason the things on your car are on there.
Everyone that is on the fence regarding EGR Google the following. EGR wiki,,,, EGR and preignition,,, and ,,, https://www.motor.com/magazine-summary/driveability-corner-oct-2012/

https://www.aa1car.com/library/egr.htm

my 1985 305 c10 runs way better with it.
 
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SASKCHEYENNE75

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Sounds like all that carb spraying and parts removing bit ya.That spraying certainly can but you can use it to check for vac leaks if you do it methodically
Absolutely....fix the no power issue first then get to the vacuum issue
 

Octane

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If anyone wants to use an exhaust gas recirculation valve that is "planet" concious.But all it does is burn exhaust gas over again and less emission output.But really all they are is a big vacuum leak,that's how they work technically.But back in the day about a trillion people removed/ disabled them,partly because of malfunction.They screw up and it'll let you know.That said,it's not a big deal to leave them alone.My gang always hotrodded the engines,went to non- egr type intakes.I remember converters being gutted or removed,fuel necks being cut out etc.The biggest deal years ago unlike nowdays was the very restrictive converters.Lots of the old motors we got the egr was already failed/ plugged/ removed etc.And those stupid smog pumps...omg! When we went to unleaded gas because of the fed. regs on pollution they had to run converters and that required unleaded fuel.No lead meant valve seat recession till they started hardening the valve seats.
 

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If anyone wants to use an exhaust gas recirculation valve that is "planet" concious.But all it does is burn exhaust gas over again and less emission output.But really all they are is a big vacuum leak,that's how they work technically.But back in the day about a trillion people removed/ disabled them,partly because of malfunction.They screw up and it'll let you know.That said,it's not a big deal to leave them alone.My gang always hotrodded the engines,went to non- egr type intakes.I remember converters being gutted or removed,fuel necks being cut out etc.The biggest deal years ago unlike nowdays was the very restrictive converters.Lots of the old motors we got the egr was already failed/ plugged/ removed etc.And those stupid smog pumps...omg! When we went to unleaded gas because of the fed. regs on pollution they had to run converters and that required unleaded fuel.No lead meant valve seat recession till they started hardening the valve seats.

Technically they work as described in the articles I linked too. Not at all like a vacuum leak, and not at all like trying to burn exhaust gas over again. And many engines will ping with the EGR disconnected my 85 c10 305 is one.
 

Bextreme04

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If anyone wants to use an exhaust gas recirculation valve that is "planet" concious.But all it does is burn exhaust gas over again and less emission output.But really all they are is a big vacuum leak,that's how they work technically.But back in the day about a trillion people removed/ disabled them,partly because of malfunction.They screw up and it'll let you know.That said,it's not a big deal to leave them alone.My gang always hotrodded the engines,went to non- egr type intakes.I remember converters being gutted or removed,fuel necks being cut out etc.The biggest deal years ago unlike nowdays was the very restrictive converters.Lots of the old motors we got the egr was already failed/ plugged/ removed etc.And those stupid smog pumps...omg! When we went to unleaded gas because of the fed. regs on pollution they had to run converters and that required unleaded fuel.No lead meant valve seat recession till they started hardening the valve seats.

The reality is that there are some specific uses and times where it is useful. They are so old and ragged out with no-one doing maintenance or cleaning on the system that it doesn't make a ton of difference to most drivers now and is easier to remove then repair/maintain.

As Ricko pointed out though, there are some benefits and hardly any downside to keeping the EGR functioning in a mostly stock setup. The biggest benefit is the 1-2mpg increase in highway fuel mileage you are likely to see from the replacement of 50% of the combustible fuel/air mixture in the cylinder with non-combustible exhaust gas. It serves a similar function to the cylinder deactivation that happens in modern LS engines. You don't need the extra power at cruise so it keeps the cylinder temps down and fuel consumption down. Modern cats are the same kind of deal. People cut them out or knock the guts out because they don't understand the concept and what is going on. The older pellet cats were hot garbage and prone to getting clogged up. A modern high flow cat will induce almost no restriction in the exhaust and gets you almost no improvement when removed. Often it screws with the EFI system enough to make it run significantly worst in fact.
 

Bextreme04

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Technically they work as described in the articles I linked too. Not at all like a vacuum leak, and not at all like trying to burn exhaust gas over again. And many engines will ping with the EGR disconnected my 85 c10 305 is one.

Exactly. An engine set up for EGR will not run right unless it is adjusted to work without it. It needs to be adjusted when the EGR is removed. Same thing with removing or modifying the catalytic converter, same thing with running a different octane of fuel also.
 

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Exactly. An engine set up for EGR will not run right unless it is adjusted to work without it. It needs to be adjusted when the EGR is removed. Same thing with removing or modifying the catalytic converter, same thing with running a different octane of fuel also.

Correct my 305 has to have some timing pulled so it doesn't ping, then power is down, so is mpg from the retarded timing so a double hit on the mpg. One from no EGR the second from the retarded timing.And as my giant benefit from this the truck has less power due to the retarded timing.I just hooked the EGR valve back up.I can live with more power and better MPG even if it does help the planet

The guys with boosted LSs are starting to realize they can fight detonation with EGR. The stuff I linked to is good reading material.
 

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