1984 egr delete question
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
Likes: 1
From: airmont new york
1984 egr delete question
hello, ive found good info for every c4 except 1984..
question is if i delete the egr with a block off plate do i need to reprogram ECM since there are no codes (32) for 1984 c4...Anything else im missing besides vacuum lines?
thanx
question is if i delete the egr with a block off plate do i need to reprogram ECM since there are no codes (32) for 1984 c4...Anything else im missing besides vacuum lines?
thanx
Le Mans Master
Joined: Aug 2017
Posts: 6,928
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From: New Jersey
I drove mine with it disconnected for a little while. It occasionally ran a little weird. Without get you'll get slightly hotter combustion chamber temps as the exhaust helps cool it a little. The plate and vacuum lines should be sufficient.
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
Likes: 1
From: airmont new york
Basically im better leaving it on? Ive read about the hotter temps and such but I havnt read anything from anyone that it actually caused any adverse effects..
Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
Technically, removing the EGR w/o re-tuning the ECM could/should result in pinging at part throttle/cruising -the mode during which the EGR should be functioning.
In reality, I disabled mine (left it in place) and saw no negative effects.
In reality, I disabled mine (left it in place) and saw no negative effects.
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
Likes: 1
From: airmont new york
thanx for your input.i will leave it off for now and see how it goes..
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
Likes: 1
From: airmont new york
Le Mans Master
Joined: Aug 2017
Posts: 6,928
Likes: 1,486
From: New Jersey
All it did was give me a slight idle surge, other than that no issues. It did run hotter. Usually in the cold it's down against the thermostat but it stayed around 5 degrees warmer than it and seemed to creep up faster at idle. Not nothing I'd write home about. since it all works I left it attached. Just trouble shooting was all.
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
Likes: 1
From: airmont new york
All it did was give me a slight idle surge, other than that no issues. It did run hotter. Usually in the cold it's down against the thermostat but it stayed around 5 degrees warmer than it and seemed to creep up faster at idle. Not nothing I'd write home about. since it all works I left it attached. Just trouble shooting was all.
hey thanx..just curious where in jersey are you..im in wayne (passaic county)
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Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,214
From: Park City Utah
All it did was give me a slight idle surge, other than that no issues. It did run hotter. Usually in the cold it's down against the thermostat but it stayed around 5 degrees warmer than it and seemed to creep up faster at idle. Not nothing I'd write home about. since it all works I left it attached. Just trouble shooting was all.
1. The EGR should be completely at idle, anyway. So there should be zero diff EGR on or off, at idle.
2. EGR shouldn't have any meaningful impact on coolant temps.
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
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From: airmont new york
hey Tom, quick question..the fact that combustion temps go up without EGR connected..Would that temp change show up as higher coolant temp reading or no?
Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
I've never seen that...and no it shouldn't anyway. I've heard others claim the opposite; dumping "hot exhaust into the intake heats the engine up". Neither is true, in a measurable or meaningful way. Car requires x amount of hp to cruise down the road at any given speed. If EGR opens, power goes down, you have to open the throttle more to maintain speed. Net result is same hp made at same RPM, same total heat. PEAK combustion temps may lower some, which reduces emissions (NOx), but net power and heat should be the same.
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
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From: airmont new york
I've never seen that...and no it shouldn't anyway. I've heard others claim the opposite; dumping "hot exhaust into the intake heats the engine up". Neither is true, in a measurable or meaningful way. Car requires x amount of hp to cruise down the road at any given speed. If EGR opens, power goes down, you have to open the throttle more to maintain speed. Net result is same hp made at same RPM, same total heat. PEAK combustion temps may lower some, which reduces emissions (NOx), but net power and heat should be the same.
ok. so basically all i have to worry about is pinging..long as that doesnt occur i should be safe..
Le Mans Master
Joined: Aug 2017
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From: New Jersey
2. And technically it should, you're providing less oxygen by adding in the exhaust gas, it's effectively slowing the burn rate so you should have lower cylinder temps. If you can measure that or not is another story. (I'm agreeing with you, see below)
That all being said I was paranoid as hell having it disconnected because people told me about melting pistons, excessive pinging etc that I may have tuned into an anomaly that wasn't actually there.
I've messed with so many other vehicles and changed so many things on all of them since I did that I may not even be remembering the right car at this point. Between school and that and all the family issues I've been dealing with I'm just about burnt out. Sorry everyone. Need to think a little more before I speak.
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
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From: airmont new york
1. On mine the egr valve always opened slightly at idle as the engine warmed up.
2. And technically it should, you're providing less oxygen by adding in the exhaust gas, it's effectively slowing the burn rate so you should have lower cylinder temps. If you can measure that or not is another story. (I'm agreeing with you, see below)
That all being said I was paranoid as hell having it disconnected because people told me about melting pistons, excessive pinging etc that I may have tuned into an anomaly that wasn't actually there. I've messed with so many other vehicles and changed so many things on all of them since I did that I may not even be remembering the right car at this point. Between school and that and all the family issues I've been dealing with I'm just about burnt out. Sorry everyone. Need to think a little more before I speak.
2. And technically it should, you're providing less oxygen by adding in the exhaust gas, it's effectively slowing the burn rate so you should have lower cylinder temps. If you can measure that or not is another story. (I'm agreeing with you, see below)
That all being said I was paranoid as hell having it disconnected because people told me about melting pistons, excessive pinging etc that I may have tuned into an anomaly that wasn't actually there.
I've messed with so many other vehicles and changed so many things on all of them since I did that I may not even be remembering the right car at this point. Between school and that and all the family issues I've been dealing with I'm just about burnt out. Sorry everyone. Need to think a little more before I speak.no problem...hope all works out for you..
Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
Don't be sorry man. Everyone's input on these forums is helpful...your input is too!
Le Mans Master
Joined: Aug 2017
Posts: 6,928
Likes: 1,486
From: New Jersey
Correct.
Something was wrong with it then, or more accurately, something was wrong with the control solenoid. That is not how it's supposed to operate. EGR shouldn't be open at idle.
You're not providing less oxygen. When EGR starts to function, you're going to depress the gas pedal...that opens throttle plates, and lets in more...oxygen. You need to do that in order to maintain the same speed. If you only open EGR and nothing else changed, car would slow down.
Don't be sorry man. Everyone's input on these forums is helpful...your input is too!
Something was wrong with it then, or more accurately, something was wrong with the control solenoid. That is not how it's supposed to operate. EGR shouldn't be open at idle.
You're not providing less oxygen. When EGR starts to function, you're going to depress the gas pedal...that opens throttle plates, and lets in more...oxygen. You need to do that in order to maintain the same speed. If you only open EGR and nothing else changed, car would slow down.
Don't be sorry man. Everyone's input on these forums is helpful...your input is too!
Thread Starter
Instructor
Joined: Mar 2018
Posts: 128
Likes: 1
From: airmont new york
Correct.
Something was wrong with it then, or more accurately, something was wrong with the control solenoid. That is not how it's supposed to operate. EGR shouldn't be open at idle.
You're not providing less oxygen. When EGR starts to function, you're going to depress the gas pedal...that opens throttle plates, and lets in more...oxygen. You need to do that in order to maintain the same speed. If you only open EGR and nothing else changed, car would slow down.
Don't be sorry man. Everyone's input on these forums is helpful...your input is too!
Something was wrong with it then, or more accurately, something was wrong with the control solenoid. That is not how it's supposed to operate. EGR shouldn't be open at idle.
You're not providing less oxygen. When EGR starts to function, you're going to depress the gas pedal...that opens throttle plates, and lets in more...oxygen. You need to do that in order to maintain the same speed. If you only open EGR and nothing else changed, car would slow down.
Don't be sorry man. Everyone's input on these forums is helpful...your input is too!
much appreciated
