EGR valve ???
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,981
Likes: 0
From: Houston,Tx. USA
EGR valve ???
Can someone discuss the operation and purpose of the EGR valve and the associated switch; all I know is I think it activates when the motor reaches operating temp. I think a bad EGR may be the source of slight to moderate pinging after getting the motor very warm. What is accomplished when the valve activates?
Instructor
Joined: Jun 2005
Posts: 109
Likes: 0
From: NH
As you probably are aware EGR stands for exhaust gas recirculation. And basically all it does is allow exhaust gas into the intake manifold under certian warm operating conditions to cool combustion chamber temps.
If the egr is not opening it could cause pinging. A simple way to test the EGR is at idle put a vacuum pump on the vacuum connection and pump away. If it is opening properly the car will stall because the inert CO2 of the exhaust gas is entering the cylinders when it shouldn't.
People run without EGR valves all the tiem without any problems, but you may have to switch to a higher octane fuel. What are you currently running?
Let me know if I'm way off base.
If the egr is not opening it could cause pinging. A simple way to test the EGR is at idle put a vacuum pump on the vacuum connection and pump away. If it is opening properly the car will stall because the inert CO2 of the exhaust gas is entering the cylinders when it shouldn't.
People run without EGR valves all the tiem without any problems, but you may have to switch to a higher octane fuel. What are you currently running?
Let me know if I'm way off base.
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,981
Likes: 0
From: Houston,Tx. USA
I'musing 93 at the pump, but you are on to something, cause when I added some 104 it lessened the issue.
I have an EGR on the way; I would just like to get back to a motor like in the 60's without as much BS!
I have an EGR on the way; I would just like to get back to a motor like in the 60's without as much BS!
Racer
Joined: Nov 2002
Posts: 359
Likes: 0
Originally Posted by SomeSayIllFixIt
As you probably are aware EGR stands for exhaust gas recirculation. And basically all it does is allow exhaust gas into the intake manifold under certian warm operating conditions to cool combustion chamber temps.
If the egr is not opening it could cause pinging. A simple way to test the EGR is at idle put a vacuum pump on the vacuum connection and pump away. If it is opening properly the car will stall because the inert CO2 of the exhaust gas is entering the cylinders when it shouldn't.
People run without EGR valves all the tiem without any problems, but you may have to switch to a higher octane fuel. What are you currently running?
Let me know if I'm way off base.
If the egr is not opening it could cause pinging. A simple way to test the EGR is at idle put a vacuum pump on the vacuum connection and pump away. If it is opening properly the car will stall because the inert CO2 of the exhaust gas is entering the cylinders when it shouldn't.
People run without EGR valves all the tiem without any problems, but you may have to switch to a higher octane fuel. What are you currently running?
Let me know if I'm way off base.
Instructor
Joined: Jun 2005
Posts: 109
Likes: 0
From: NH
I believe that this car should not be ecm controlled, at least my 80 isn't- unless I'm totally messed- you are right that it will be seeing vacuum at all times unless it is running off ported vacuum, I have no idea what it is supposed to be running on, as far as vacuum is concerned.
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Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,981
Likes: 0
From: Houston,Tx. USA
Originally Posted by Avette4me
take it off and block the hole...
There seems to be some other "plumbing" associated with it.
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
Originally Posted by Chopper Larry
That's what I would like to do.....is it a pipe thread type plug?
There seems to be some other "plumbing" associated with it.
There seems to be some other "plumbing" associated with it.
Race Director
Joined: Sep 2002
Posts: 10,362
Likes: 5
From: San Diego - Deep Within The State of CONFUSION!
Originally Posted by Avette4me
take it off and block the hole...
Bad idea and poor advice. EGR helps emissions at no cost to you or your engine. On the plus side, you have cooler combustion chamber temps and less propensity to ping. On the minus side, you have the 'objection' to conform to smog laws. That's all. Like a PCV valve, an EGR hurts nothing but only helps you.
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
Originally Posted by SanDiegoPaul
Bad idea and poor advice. EGR helps emissions at no cost to you or your engine. .
.
Originally Posted by SanDiegoPaul
On the minus side, you have the 'objection' to conform to smog laws..
Last edited by Avette4me; Oct 15, 2005 at 09:33 PM.
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Originally Posted by Russ Bellinis
You are close. One other thing to add is that egr only operates at part throttle if you have an ecm. If your car is pre computer control, egr probably operates all of the time I'm not sure on those. On an ecm car, the egr turns on with a warm engine under light load conditions. It cools the combustion chambers, and reduces nox emissions. What is neat is that it allows the use of lower octane fuels with high compression engines on the street. Of course if you take it to the track, you want to run some high octane race gas so the ecm won't see knocks and pull timing.
BigBlockk
Later.....
Racer
Joined: Jan 2003
Posts: 383
Likes: 0
From: Columbia SC
If the EGR is operating properly there is no good reason to remove it unless you want to race. For street performance leave it in and 93 octane fuel should be ok if your distributor and base timing are setup properly.
I read you have a new EGR coming, good, this will give you a chance to make sure the openings in the intake manifold are clean when you replace the old EGR.
Also make sure the vac hose is connected to the proper place. Otherwise the EGR may get vac at the wrong time and open when it should not.
Like someone already said if it is setup properly you will not know the EGR is working except for no knocking and you can run lower octane fuel and less bad stuff coming out of the exhaust, all good things.
I read you have a new EGR coming, good, this will give you a chance to make sure the openings in the intake manifold are clean when you replace the old EGR.
Also make sure the vac hose is connected to the proper place. Otherwise the EGR may get vac at the wrong time and open when it should not.
Like someone already said if it is setup properly you will not know the EGR is working except for no knocking and you can run lower octane fuel and less bad stuff coming out of the exhaust, all good things.
Safety Car
Joined: Jan 2004
Posts: 4,776
Likes: 142
From: North of Atlanta GA
St. Jude Donor '05
If you push in on the diaphram of the EGR and it stays in and you blow into the stem where the vaccuum hose connects to it and the diaphram returns to orig. position does that mean it's working properly?
Safety Car
Joined: Jan 2004
Posts: 4,776
Likes: 142
From: North of Atlanta GA
St. Jude Donor '05
Originally Posted by SomeSayIllFixIt
As you probably are aware EGR stands for exhaust gas recirculation. And basically all it does is allow exhaust gas into the intake manifold under certian warm operating conditions to cool combustion chamber temps.
If the egr is not opening it could cause pinging. A simple way to test the EGR is at idle put a vacuum pump on the vacuum connection and pump away. If it is opening properly the car will stall because the inert CO2 of the exhaust gas is entering the cylinders when it shouldn't.
People run without EGR valves all the tiem without any problems, but you may have to switch to a higher octane fuel. What are you currently running?
Let me know if I'm way off base.
If the egr is not opening it could cause pinging. A simple way to test the EGR is at idle put a vacuum pump on the vacuum connection and pump away. If it is opening properly the car will stall because the inert CO2 of the exhaust gas is entering the cylinders when it shouldn't.
People run without EGR valves all the tiem without any problems, but you may have to switch to a higher octane fuel. What are you currently running?
Let me know if I'm way off base.
Racer
Joined: Jan 2003
Posts: 383
Likes: 0
From: Columbia SC
Originally Posted by pcfred
If you push in on the diaphram of the EGR and it stays in and you blow into the stem where the vaccuum hose connects to it and the diaphram returns to orig. position does that mean it's working properly?
Safety Car
Joined: Jan 2004
Posts: 4,776
Likes: 142
From: North of Atlanta GA
St. Jude Donor '05
Originally Posted by Pete76Shark
Pull off the old EGR valve and clean out the cloged up ports on the intake manifold.