And then there's this thing...

[thedoctor]

I hope this is interesting for some of you experienced mechanics. I really appreciate the information. I really want to understand the entire vacuum system and what is essential to the engine running and what is less so.

[AKghandi]

egr vacuum solenoid it controls the egr valve.

[thedoctor]

Thank you. This gives me a place to start with it.

[noahkort]

Where can I find one of these? Can I drive the car without it in the interm, I busted it trying to take the hose off of the nipple. Which on mine is plastic, despite it appearing metal in your picture.  If I do plan to drive it without the control valve do I need to plug up the entire EGR?  (84 gl 1800, hatchback)

\

Thanks!

[CarpeNoctem]

That could depend on a few factors. Do you live in an area where emissions tests are mandatory? If so then  an EGR valve is a needed piece of emissions equipment and will be expected to be there in operational order to pass. On the other hand, IF you don't live in an emissions testing area you could completely remove it as it is just another part to go wrong and cause vacuum leaks and stuck open/slightly open valves are a plague of rough running cars and robs power by directing exhaust gasses into the intake charge.

 

in that situation you'll want to remove it's whole system which includes the EGR valve, the solenoid and the vac line. removing the EGR valve it's self will require a block off plate. I've never seen one for these engines but they are easy to make. Take an egr mounting gasket get a shop to cut some decently thick steel/aluminum to the shape (or do it yourself as it's not hard if you have the tools) drill the bolt holes using the gasket to mark them. apply the gasket and plate and bolt it down. viola you just removed a system that can cause driveability issues.

 

As an emissions inspector in Nevada I have to look for these and fail cars that have em blocked off. so make sure you dont live in an area it's needed or aren't moving to one soon. it can always be replaced though.

 

Most commonly tuned cars will have pre-made aftermarket block off plates like this 

 

 

 

Check and see if our egr valves are used by any other manufacturers that might have a more common aftermarket. we might have em available just because the gasket area and bolt pattern matches. 

 

 

For my own cars I use two gaskets underneath and a bit of coke can in between them with everything hooked up like normal and silicone in the nipple to clog it off. But that's because my system has to "appear functional" out here. before going that route you have to make sure your county doesn't do a "function test". which is basically just hooking a hand operated vacuum pump up to the egr with the engine running and seeing if the engine stumbles when vacuum is applied and the valve is open at idle (only supposed to open during low load/high vacuum times a.k.a. cruising). anyhow that's probably more info than you needed.

Edited November 18, 2013 by CarpeNoctem

[Gloyale]

EGR valve should not be eliminated.

 

It keeps cylinder temps lower.  You won't get any more power or mileage without so just leave it OK?

 

You can replace that solenoid with one from many types of newer japanese cars, toyota, honda, newer subarus etc.  It's simply open to vacuum(when activated), or open to atmosphere(when off).

[CarpeNoctem]

it lowers cylinder temps by recirculating exhaust gasses into the intake causing a temporary rich condition (because of the amount of oxygen being displaced). the level it drops cylinder temps is negligible when considering component life. the reason for it isn't to keep cylinders cool it's to keep the cylinders just cool enough to prevent the formation of oxides of nitrogen or NOx. it does not reduce it even near any level the promotes longer engine life. that was never the purpose of the egr system

[yblocker]

That is an electrically operated solenoid vacuum switch.

Your EA82 has two of them.

One controls the EGR valve, the other one controls the vapor canister flow.  Each one has its specific connector.

They can be tested by measuring the resistance between the terminals (I think about 30 ohms).  And they should click when 12v is applied.

They are failure prone, hard to find now and expensive.  

The junkyard is full of 80's 90's cars that use similar vacuum switches that can be used instead, though i have several of the old style in reserve.

[CarpeNoctem]

that said you won't be running under false rich conditions so the engine is actually using the fuel to a better potential so you will be using less throttle to keep the engine at the same cruising speed the EGR system is made to operate at so you will infact be getting (slightly) better mpg. 

[l75eya]

 

You can replace that solenoid with one from many types of newer japanese cars, toyota, honda, newer subarus etc. It's simply open to vacuum(when activated), or open to atmosphere(when off).

+1. I replaced my solenoid with one I snagged out of a ford tempo.

[Gloyale]

that said you won't be running under false rich conditions so the engine is actually using the fuel to a better potential so you will be using less throttle to keep the engine at the same cruising speed the EGR system is made to operate at so you will infact be getting (slightly) better mpg. 

 

This is a myth.

 

Blocking your EGR won't help mileage, or power.  It will cause higher temps (by some amount...not going argue)

 

EGR is not meant for cruising speed.  If your EGR is opening while cruiseing/low throttle then something is wrong.

 

EGR opens mostly only at wide throttles, when under load. This is why it's connected to Above throttle vacuum, not intake vacuum.

 

FSM clearly states this and that's why you can watch them operate when you rev the engine above 3500 rpms quickly.  They operate when Above throttle vacuum is high.....which is under load, not simply cruising.  At cruising, light throttle, above throttle vacuum is very low.

 

You clearly don't understand them...... no wonder you think it's best to "delete"

Edited November 19, 2013 by Gloyale

[noahkort]

guys thanks for all the info, i'm starting to understand the different views on the EGR valve.

 

My question is: Can I drive around without the egr solenoid control, just in the interm, while I work out replacing it.

if so: should I plug the line or leave it open? I am mostly cruising where I live.

 

Hell I'll just run the line into the cab of the car and open and close it manually if it means I can drive my car.  So is it open or closed when cruising.

[ferox]

guys thanks for all the info, i'm starting to understand the different views on the EGR valve.

 

My question is: Can I drive around without the egr solenoid control, just in the interm, while I work out replacing it.

if so: should I plug the line or leave it open? I am mostly cruising where I live.

 

Hell I'll just run the line into the cab of the car and open and close it manually if it means I can drive my car.  So is it open or closed when cruising.

You should be fine as long as you disconnect the vacuum supply hose and cap it so you don't have a vacuum leak.  The hose that goes to the egr can just be removed for the time being.

 

I would actually just eliminate the solenoid altogether, but that's your call.

[CarpeNoctem]

Gloyale welcome to flaming at a new member you don't know about yet.

 

[ ]

 

 

i'm going to start with NON me sources because honestly though my words will be civil and language clean, auto forums have become so "clique-y" anymore somehow I figure this will be me getting banned which is a shame because (other than people who think long years on it means godhood) it's a very good forum and source of info. Yes you know these cars better due to length of ownership, but you don't know it all and you preach as if you do.

 

 

Wiki

 

EGR is typically not employed at high loads because it would reduce peak power output. This is because it reduces the intake charge density. EGR is also omitted at idle (low-speed, zero load) because it would cause unstable combustion, resulting in rough idle. (THUS it is utilized at low throttle and cruising)

 

Auburn university's Diagnostic Quarterly:

The ABCs of EGR http://www.ag.auburn.edu/~parmega/efi/egr.txt

 

The EGR valve opens during light throttle and warm engine cruising and
channels the exhaust gases back into the engine's inlet air.

 

autoshop101 .com

http://www.autoshop101.com/forms/h61.pdf (pdf so not pasteable. middle of 

 

lousiana.gov emissions classes  (any yes it argues mpg but there are varied ongoing arguments on this topic) 

 

Because the E.G.R. system only operates at cruise speeds, fuel economy is not negatively affected unless the system malfunctions.

 

 

 

 

NOW on to me 

 

12 1/2 years in the automotive field

Associates degree in applied technology (automotive)

T.S.E.P. Internship Graduate (acdelco's private intensive training)

1G emissions inspector

Former hot rod builder and lead tech for Gerner Design

Former Bike builder for American Performance Cycle

Former warranty department manager/tecnical support/R&D assistant/public relations  in automotive aftermarket for Air-Zenith

 

and that is aside from time working as a standard mechanic.

 

 

 

 

 

YOU are the person who doesn't know what your on about. Just because I've had limited exposure to this particular engine and am open enough to ask questions doesn't mean I don't know the field.

 

[/  ]

Edited November 21, 2013 by CarpeNoctem

[CarpeNoctem]

Apologies "thedoctor" for taking care of that in your thread. It IS ultimately up to you what you do with your car. again, sorry for that.

[Gloyale]

Gloyale welcome to flaming at a new member you don't know about yet.

 

[ ]

 

 

i'm going to start with NON me sources because honestly though my words will be civil and language clean, auto forums have become so "clique-y" anymore somehow I figure this will be me getting banned which is a shame because (other than people who think long years on it means godhood) it's a very good forum and source of info. Yes you know these cars better due to length of ownership, but you don't know it all and you preach as if you do.

 

 

Wiki

 

Auburn university's Diagnostic Quarterly:

The ABCs of EGR http://www.ag.auburn.edu/~parmega/efi/egr.txt

 

autoshop101 .com

http://www.autoshop101.com/forms/h61.pdf (pdf so not pasteable. middle of 

 

lousiana.gov emissions classes  (any yes it argues mpg but there are varied ongoing arguments on this topic) 

 

 

 

 

NOW on to me 

 

12 1/2 years in the automotive field

Associates degree in applied technology (automotive)

T.S.E.P. Internship Graduate (acdelco's private intensive training)

1G emissions inspector

Former hot rod builder and lead tech for Gerner Design

Former Bike builder for American Performance Cycle

Former warranty department manager/tecnical support/R&D assistant/public relations  in automotive aftermarket for Air-Zenith

 

and that is aside from time working as a standard mechanic.

 

 

 

 

 

YOU are the person who doesn't know what your on about. Just because I've had limited exposure to this particular engine and am open enough to ask questions doesn't mean I don't know the field.

 

[/  ]

 

 

Okay.....be mad all you want.  Doesn't bother me.

 

BUt you might not want to brag about being an Emmisions tester and then telling people to get rid of their emmisions equipment.

 

Heck you go one step further and admit your OWN vehichle has been modified, in a deceptive way, to "Fool" the inspectors.

 

So.....your the inspector?  wouldn't that make you the fool too???

 

You should be fired.

[86 Wonder Wedge]

Not to get into the middle of this, but some EGR valves cannot simply be actuated by applying vacuum (essentially a "bench" test) and I'm not including the GM (among others) ones that are all electronic.

 

While EGR is by no means required to maintain, operate an engine or even improve emissions, a properly functioning system has ZERO negative impact upon the operation of the engine. Who doesn't want better efficiency, longer component life and reduced emissions?

 

That being said, different engines deploy and integrate this system differently.

 

On my 81 Firebird (with the CCC), EGR only opens at part throttle, at operating temp, while moving (from the FSM). They go on to explain this is because the O2 sensor needs to be up to operating temperature (which only happens after sustained, off-idle RPMs) and so the engine is up to operating temp. If you run the EGR while the engine is in open-loop rich mode, it will cause unmetered air/unburnt fuel back into the intake and cause unstable operation.

 

I surmise the Subaru system is similar (due to the unheated O2, the SPFI and unmetered exhaust gas flow).

 

Back to OP: That's the EGR solenoid. It allows vacuum to the valve to open it when the ECU deems necessary. When it closes, it vents to atmosphere through the small, black cap so the valve closes again.

Edited November 21, 2013 by 86 Wonder Wedge

[CarpeNoctem]

Yes I have in the past had my own cars outside local regulation. Are any of them now? No. I test my own cars so should the dmv decide to take notice of it (even though it is allowed). My cars are all within regulations to even the most thorough inspection. I did that stuff BEFORE I worked as an inspector. I'm not a hippocrite like that. Go ahead and call the las vegas dmv emissions lab and have em pull me in. Nothing to hide.

 

As for the person asking questions I said it was an option if he lived in a non emissions area.

[CarpeNoctem]

Wonder wedge you're correct on the system design simularities. That's the reason for the solenoid to prevent actuation until criteria have been met.

[Gloyale]

For my own cars I use two gaskets underneath and a bit of coke can in between them with everything hooked up like normal and silicone in the nipple to clog it off. But that's because my system has to "appear functional" out here.

 

Nothing here to indicate past tense

[ford'ssubaru's]

You know fellows I am a retired NAVY construction mechanic,  Heavy equipment mechanic currently and just enjoy learning from you all without pulling down your pants and trying to figure out who's is bigger.  That is all.  Carry on...:-)

[86 Wonder Wedge]

You know fellows I am a retired NAVY construction mechanic,  Heavy equipment mechanic currently and just enjoy learning from you all without pulling down your pants and trying to figure out who's is bigger.  That is all.  Carry on...:-)

 

Wait, you can learn with pants... ON? What?

 

[ford'ssubaru's]

Wait, you can learn with pants... ON? What?

 

I sense sarcasm from one one the lesser branches of the military..........  My military radar is sensing Marine.......LOL.

[ivans imports]

I would use a egr soiliniod from a outback dose same job and way easyer to find and dosent fail as mutch quwick fix whats with all the tickets ? I been a licenced tech for ten years and have been working on subarus for 18 years.

[1983wagon]

The blokes here to get info. Not get a history lesson on your damn life.