Why not Disable EGR switch/system?
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 6,341
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From: Shelton CT
Why not Disable EGR switch/system?
I just started getting a Code32 during lenghty drive on the highway, my EGR has been replaced about 2yrs ago, but I might replace my switch next to the distributor. (I don't want to take off the plenum/intake again, just put it back on.)
Why don't I (we) just disable this? Do we really NEED it?
Doesn't it hurt performance a bit?
If you unplug the connector from the vacuum connector (or remove the vacuum hose), and get the code, and then remove the EGR check form the CHIP, would the car still run fine? I mean it wouldn't run in 'limp-home' mode would it?
Thanks in advance
Why don't I (we) just disable this? Do we really NEED it?
Doesn't it hurt performance a bit?
If you unplug the connector from the vacuum connector (or remove the vacuum hose), and get the code, and then remove the EGR check form the CHIP, would the car still run fine? I mean it wouldn't run in 'limp-home' mode would it?
Thanks in advance
Race Director
Joined: Mar 2002
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Re: Why not Disable EGR switch/system? (MrNuke)
i removed mine, pluged the vacuum hose, unhooked the electrical and never had a problem, when i had my chip burned the i told the guy about it and he factored that into my chip, i haven't had a problem yet, it runs good and hard. before i removed anything i inquired on here and the consensus was that as long as you unhook the electrical and plug the hose you probably won't even see a code :cheers:
Burning Brakes
Joined: Dec 2001
Posts: 901
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From: Punta Gorda, FL
Re: Why not Disable EGR switch/system? (MrNuke)
No can do for me, live in an area with emissions testing. EGR cools the combustion temps. Apparently, no damage is done with it disconnected since so many people do it. I have run the car with it disconnected and didn't notice any difference. If you disconnect the vacuum line at the value and block the line and the valve you won't get a code.
None of this is going to solve your code 32, however. A number of factors have to be in effect to set. Happened to me only once. I can check the manual for you if you want, let me know. lspalding@ameritech.net.
None of this is going to solve your code 32, however. A number of factors have to be in effect to set. Happened to me only once. I can check the manual for you if you want, let me know. lspalding@ameritech.net.
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 6,341
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From: Shelton CT
Re: Why not Disable EGR switch/system? (lspalding)
It's probably my egr switch next to the distributor (the plastic vacuum switch). It has been moved around the past few weeks with the new intake was put on and things changed. It doesn't seem to hurt my performance, but after it sends a code and the SES light comes on, the car feels a bit sluggish I 'think'.. Gonna check the vacuum hoses and wires tomorrow to make sure nothign got disconnected..The code JUST started, since I put my stock '85 chip back in my car... I had a performance resources chip in there before, but with the stock chip the car feels even faster.. wierd.. :D
Racer
Joined: Apr 2002
Posts: 415
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From: loughborough Leics ENGLAND
Re: Why not Disable EGR switch/system? (MrNuke)
What do i need to do the remove egr on my 90 ?
I can not remember seeing any wires got to an egr sensor :confused:
I want to lose the egr system when i fit my 2151 headers :D
:cheers:
I can not remember seeing any wires got to an egr sensor :confused:
I want to lose the egr system when i fit my 2151 headers :D
:cheers:
Intermediate
Joined: May 2002
Posts: 32
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Re: Why not Disable EGR switch/system? (MrNuke)
Yes it hurts performance; it's the performance equivalent of (you'll pardon the expression) p*ssing in your soup.
The only positive thing it does is reduces your fuel octance requirements at part throttle - but then that's what the knock sensor is for.
Disconnecting or plugging the vacuum line to the EGR valve doesn't hurt a thing. I blocked mine about 6 years and 50,000 miles ago.
Regards,
- R
The only positive thing it does is reduces your fuel octance requirements at part throttle - but then that's what the knock sensor is for.
Disconnecting or plugging the vacuum line to the EGR valve doesn't hurt a thing. I blocked mine about 6 years and 50,000 miles ago.
Regards,
- R
Race Director
Joined: Sep 2001
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From: NEwhere Ohio
Re: Why not Disable EGR switch/system? (Redbob45)
I thought it only functions at part throttle, and at WOT it is closed.
So it theoretically wouldn't affect WOT runs, 1/4 times or anything.
So it theoretically wouldn't affect WOT runs, 1/4 times or anything.
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From: Stafford, Virginia Kittah, Kittah, Kittah...
Re: Why not Disable EGR switch/system? (MrNuke)
Interestingly I had this happen on my old TPI IROC on a cross country drive from CA to GA several years back...
While I didn't notice any performance gains, the car did get about 3mpg more without the EGR than it did with... In GA I had the car repaired and I lost my 3mpg increase...
If it wasn't for the SES light, I would have left it... From what I remeber about the old TPI setup, the switch controls the vacuum to the EGR valve... With my failed switch, the EGR was never activated...
While I didn't notice any performance gains, the car did get about 3mpg more without the EGR than it did with... In GA I had the car repaired and I lost my 3mpg increase...
If it wasn't for the SES light, I would have left it... From what I remeber about the old TPI setup, the switch controls the vacuum to the EGR valve... With my failed switch, the EGR was never activated...
Race Director
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From: Stafford, Virginia Kittah, Kittah, Kittah...
Re: Why not Disable EGR switch/system? (388 SOLid RoLLeR)
LT1 guys, is it worth disconnecting???????
I didn't get a chance to do a through testing of it as far as fuel economy because I kept setting P0400...
Jim
Race Director
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Re: Why not Disable EGR switch/system? (MrNuke)
Some guys who unhook their EGR system and don't do anything else have seen some problems. Noteably bad pinging and such. There are a number of conditions that must be met before the car will enable EGR. If these conditions are not met it apparently knows how to compensate for it not being there and you won't have any trouble. In other words you need to turn it off in the computer. There isn't a quick and easy EGR diasable button anywhere, so what you have to do is change the conditions.
In my case there is an EGR Enable Coolant Temp Threshold. Set this to some ungodly number and you effectively disable EGR. Mine is set for the maximum value of 151.3 degrees celcius. Since the car never tried to call on EGR it compensates in other ways to reducing pinging and such. However, if you remove the EGR stuff it can still set a code, unless you uncheck the box for Code 32. Doing both of these will very effectively disable EGR and you can remove it entirely. You shouldn't have any driveability problems by doing this either. Now if you just rip the EGR off and don't do any programming you might have some trouble. Some people do, some don't.
In my case there is an EGR Enable Coolant Temp Threshold. Set this to some ungodly number and you effectively disable EGR. Mine is set for the maximum value of 151.3 degrees celcius. Since the car never tried to call on EGR it compensates in other ways to reducing pinging and such. However, if you remove the EGR stuff it can still set a code, unless you uncheck the box for Code 32. Doing both of these will very effectively disable EGR and you can remove it entirely. You shouldn't have any driveability problems by doing this either. Now if you just rip the EGR off and don't do any programming you might have some trouble. Some people do, some don't.
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Re: Why not Disable EGR switch/system? (MrNuke)
Here, I posted this a while back, an excellent article on just what the EGR system does. http://www.ag.auburn.edu/users/gparmer/efi/egr.txt
Burning Brakes
Joined: Feb 2000
Posts: 824
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From: Camden SC
Re: Why not Disable EGR switch/system? (92Shawnster)
Good article.
And Chiltons adds: "Too little or no EGR flow allows combustion temperatures to rise, which could result in spark knock (detonation), engine overheating and/or emissions test failure."
The ESC system should retard the timing long before you hear anything. Of course, performance decreases as you retard timing. As noted, at WOT, it closes anyway, so 1/4 mile times are really not an issue. At normal cruise is where the system really does its thing and is where most codes show up.
There are work arounds for eveything like ECM/PCM codes etc.
The system is not that complicated and easily repaired with simple vacuum checks, volt meter, visual inspection. The engine was designed to work with the system. If you have to pass emissions, you'll need the system. If you plan to sell the car to someone who needs the system, components may have to be reinstalled. Whatever.
dlmeyers 90 coupe zf6 3 speed shocks
And Chiltons adds: "Too little or no EGR flow allows combustion temperatures to rise, which could result in spark knock (detonation), engine overheating and/or emissions test failure."
The ESC system should retard the timing long before you hear anything. Of course, performance decreases as you retard timing. As noted, at WOT, it closes anyway, so 1/4 mile times are really not an issue. At normal cruise is where the system really does its thing and is where most codes show up.
There are work arounds for eveything like ECM/PCM codes etc.
The system is not that complicated and easily repaired with simple vacuum checks, volt meter, visual inspection. The engine was designed to work with the system. If you have to pass emissions, you'll need the system. If you plan to sell the car to someone who needs the system, components may have to be reinstalled. Whatever.
dlmeyers 90 coupe zf6 3 speed shocks
Le Mans Master
Joined: Mar 2001
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From: Modesto CA
Re: Why not Disable EGR switch/system? (MrNuke)
I got that code back this summer..hasn't happened since. A lot of people said it was just due to the heat outside (105º), idling in traffic. Ehh..ohh well huh? LoL
