EGR valve

Blindeye_03 · 07-04-2001, 06:55 PM

Where is it located and how do I disconnect it?
thanks,
-justin

oh, I also know I will not pass emmissions with it disconnected...

munkis · 07-04-2001, 07:13 PM

Why do you want to disconnect it, besides not passing emmission, you will lose performance and gas mileage..and the car will most likely not run.

Jay McDade
Auto Tech--Lincoln/Mercury/Jaguar
www.hometown.aol.com/impreza25rs2000

Albert · 07-04-2001, 09:14 PM

Pls correct me if I'm wrong... On the 2.5L the EGR recirculates exhaust from cylinder #4 only. The exhaust gas is fed back ONLY to cylinder#4 intake runner.
It's been a while since I "messed" with this stuff, but what we use to do on Toyota's was replace the EGR outlet gasket with a blank gasket.

Another option on our car might be to cap, and reinstall the EGR tube coming out the side of cylinder #4.

Now, the big question is will either flash a check engine light.

Proceed at your own risk.

Blindeye_03 · 07-05-2001, 01:26 AM

Well its supposed to increase preformance, because the exhaust gas will not be thrown back into the intake, thus reducing temps, and raising hp<--theoretically....my friend with a supra tt is doing this mod soon and has 'talked' me into doing it. I just want to know if I will ruin my engine?

SubyTechMaster · 07-05-2001, 03:14 AM

In case anyone is not sure how EGR works - it recycles exhaust gas back into the combustion chamber and LOWERS combustion temperature, thereby reducing NOx and also "engine knock". It does this because by the time the exhaust gas returns to the cylinder it is much cooler and since it does not burn again it absorbs heat from the cumbustion process.

If you are asking about a 2001 2.5RS, it doesn't have EGR. Only the twin cam 2.5L had EGR (phase I).

dRu18 · 07-05-2001, 01:21 PM

i swear the EGR is ONLY there for emissions. from various sources i have heard that when you plug up the egr valve you gain a LITTLE performance. just remember to unplug it when you go for smog

Albert · 07-05-2001, 04:06 PM

Ok, egr valve is only on DOHC phase 1.

What was the design reason for only recircing back to one cylinder?

SubyTechMaster · 07-05-2001, 04:25 PM

Just because the EGR appears to feed directly into the #4 runner doesn't mean it does. Actually, there is a passage cast into the intake manifold that directs the EGR to the center of the manifold where it can flow evenly to all cylinders.

And yes, if you disable EGR on any car with OBDII, it will set a code for EGR system malfunction.

Blindeye_03 · 07-05-2001, 05:36 PM

Since when is exhaust gas cold?...

Anyways...would my car run at all if I disconnected it?

SubyTechMaster · 07-05-2001, 07:32 PM

Cold is a relative decription of the amount of heat. NOx begins to form over 2500deg F.

If you are asking about your 2001 2.5RS, read the above posts, you don't have EGR. If you are asking about another vehicle, sure you car will run w/o EGR, the EGR doesn't operate full time anyway.

Albert · 07-05-2001, 08:10 PM

SubyTech Master-As always, thanks for the in-depth responses.

MrHorspwer · 07-06-2001, 12:23 AM

I agree with the master... ERG is only functioning during part throttle, cruise applications. It is closed during full throttle or quick throttle manuevers... as well as idle. Your car would run without one... it also would throw a code and your check engine light would be glowing at you if you just unplugged. Going even further than that... GM vehicles measure the flow rate through the EGR. If you just blocked the passage you would light the check engine light with an insufficient flow through the EGR DTC. I can find no good reason to disable an EGR valve and many reason not to. It is there for a reason and the engine management software is calibarated to use it.

Blindeye_03 · 07-06-2001, 04:17 AM

Well thank you for answering my question

.

ort5 · 07-06-2001, 09:42 AM

SubyTechMaster,

Do you know if 1994 Legacy Turbos had EGR valves?
I have read about deposits on these can cause issues like poor idle, poor acceleration etc. If I have one, is there a way for me to remove it to inspect it for deposits...and then clean it if need be?

Thanks,
Dave

SubyTechMaster · 07-06-2001, 11:16 AM

No, it did not. Legacy, up through 1994 did not have EGR. Impreza from 1993 to 1998 has EGR; Legacy from 1995 through 1998 (2.2L) has EGR; Legacy, Forester, Impreza w/2.5L twin cam has EGR.

skidplatez · 07-06-2001, 05:44 PM

Besides Blindeye_03, it's illegal is STS.

Blindeye_03 · 07-06-2001, 06:32 PM

Well thats good to know

.
1) it was just a question
2) I cant disconnect the EGR valve even if I wanted to, b/c MY01 impreaza's dont have it...

BTW...I need to get a SCCA solo2 rulebook...

07-04-2001, 06:55 PM	#1
Blindeye_03 Scooby Guru Member#: 4418 Join Date: Feb 2001 Chapter/Region: South East Location: Eastman, Ga. (aka Armpit Ga) Vehicle: 03 Silver Civic Si 05 Suzuki SV650	EGR valve Where is it located and how do I disconnect it? thanks, -justin oh, I also know I will not pass emmissions with it disconnected...

07-04-2001, 09:14 PM	#3
Albert Scooby Specialist Member#: 3288 Join Date: Dec 2000 Location: San Diego, CA. USA Vehicle: 1998 Impreza 2.5RS Rally Blue Pearl	Pls correct me if I'm wrong... On the 2.5L the EGR recirculates exhaust from cylinder #4 only. The exhaust gas is fed back ONLY to cylinder#4 intake runner. It's been a while since I "messed" with this stuff, but what we use to do on Toyota's was replace the EGR outlet gasket with a blank gasket. Another option on our car might be to cap, and reinstall the EGR tube coming out the side of cylinder #4. Now, the big question is will either flash a check engine light. Proceed at your own risk. Last edited by Albert; 07-04-2001 at 09:18 PM.

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07-04-2001, 07:13 PM	#2
munkis Scooby Guru Member#: 1847 Join Date: Jul 2000 Chapter/Region: Tri-State Location: brokenmotorsports.com Vehicle: Team Broken: V6 GF www.occsubarumeet.com	Why do you want to disconnect it, besides not passing emmission, you will lose performance and gas mileage..and the car will most likely not run. Jay McDade Auto Tech--Lincoln/Mercury/Jaguar www.hometown.aol.com/impreza25rs2000

07-05-2001, 01:26 AM	#4
Blindeye_03 Scooby Guru Member#: 4418 Join Date: Feb 2001 Chapter/Region: South East Location: Eastman, Ga. (aka Armpit Ga) Vehicle: 03 Silver Civic Si 05 Suzuki SV650	Well its supposed to increase preformance, because the exhaust gas will not be thrown back into the intake, thus reducing temps, and raising hp<--theoretically....my friend with a supra tt is doing this mod soon and has 'talked' me into doing it. I just want to know if I will ruin my engine?

07-05-2001, 03:14 AM	#5
SubyTechMaster Scooby Specialist Member#: 4423 Join Date: Feb 2001 Location: Placerville, CA USA Vehicle: '04 08 Tribeca, SVX Gold, Maroon	In case anyone is not sure how EGR works - it recycles exhaust gas back into the combustion chamber and LOWERS combustion temperature, thereby reducing NOx and also "engine knock". It does this because by the time the exhaust gas returns to the cylinder it is much cooler and since it does not burn again it absorbs heat from the cumbustion process. If you are asking about a 2001 2.5RS, it doesn't have EGR. Only the twin cam 2.5L had EGR (phase I).

07-05-2001, 01:21 PM	#6
dRu18 Scooby Specialist Member#: 4034 Join Date: Feb 2001 Chapter/Region: BAIC Location: Cupertino, Burlingame, Davis, Vehicle: 2005 Infiniti G35c Ivory Pearl	i swear the EGR is ONLY there for emissions. from various sources i have heard that when you plug up the egr valve you gain a LITTLE performance. just remember to unplug it when you go for smog

07-05-2001, 04:06 PM	#7
Albert Scooby Specialist Member#: 3288 Join Date: Dec 2000 Location: San Diego, CA. USA Vehicle: 1998 Impreza 2.5RS Rally Blue Pearl	Ok, egr valve is only on DOHC phase 1. What was the design reason for only recircing back to one cylinder?

07-05-2001, 04:25 PM	#8
SubyTechMaster Scooby Specialist Member#: 4423 Join Date: Feb 2001 Location: Placerville, CA USA Vehicle: '04 08 Tribeca, SVX Gold, Maroon	Just because the EGR appears to feed directly into the #4 runner doesn't mean it does. Actually, there is a passage cast into the intake manifold that directs the EGR to the center of the manifold where it can flow evenly to all cylinders. And yes, if you disable EGR on any car with OBDII, it will set a code for EGR system malfunction.

07-05-2001, 05:36 PM	#9
Blindeye_03 Scooby Guru Member#: 4418 Join Date: Feb 2001 Chapter/Region: South East Location: Eastman, Ga. (aka Armpit Ga) Vehicle: 03 Silver Civic Si 05 Suzuki SV650	Since when is exhaust gas cold?... Anyways...would my car run at all if I disconnected it?

07-05-2001, 07:32 PM	#10
SubyTechMaster Scooby Specialist Member#: 4423 Join Date: Feb 2001 Location: Placerville, CA USA Vehicle: '04 08 Tribeca, SVX Gold, Maroon	Cold is a relative decription of the amount of heat. NOx begins to form over 2500deg F. If you are asking about your 2001 2.5RS, read the above posts, you don't have EGR. If you are asking about another vehicle, sure you car will run w/o EGR, the EGR doesn't operate full time anyway.

07-05-2001, 08:10 PM	#11
Albert Scooby Specialist Member#: 3288 Join Date: Dec 2000 Location: San Diego, CA. USA Vehicle: 1998 Impreza 2.5RS Rally Blue Pearl	SubyTech Master-As always, thanks for the in-depth responses.

07-06-2001, 12:23 AM	#12
MrHorspwer Scooby Specialist Member#: 4063 Join Date: Feb 2001 Chapter/Region: MWSOC Location: Roseville, MI Vehicle: 2002 2.5 RS 1990 Mazda Miata	I agree with the master... ERG is only functioning during part throttle, cruise applications. It is closed during full throttle or quick throttle manuevers... as well as idle. Your car would run without one... it also would throw a code and your check engine light would be glowing at you if you just unplugged. Going even further than that... GM vehicles measure the flow rate through the EGR. If you just blocked the passage you would light the check engine light with an insufficient flow through the EGR DTC. I can find no good reason to disable an EGR valve and many reason not to. It is there for a reason and the engine management software is calibarated to use it.

07-06-2001, 04:17 AM	#13
Blindeye_03 Scooby Guru Member#: 4418 Join Date: Feb 2001 Chapter/Region: South East Location: Eastman, Ga. (aka Armpit Ga) Vehicle: 03 Silver Civic Si 05 Suzuki SV650	Well thank you for answering my question .

07-06-2001, 09:42 AM	#14
ort5 Scooby Newbie Member#: 3706 Join Date: Jan 2001 Location: Jaffrey, NH Vehicle: 2000 VW Golf TDI 5mt Red	SubyTechMaster, Do you know if 1994 Legacy Turbos had EGR valves? I have read about deposits on these can cause issues like poor idle, poor acceleration etc. If I have one, is there a way for me to remove it to inspect it for deposits...and then clean it if need be? Thanks, Dave

07-06-2001, 11:16 AM	#15
SubyTechMaster Scooby Specialist Member#: 4423 Join Date: Feb 2001 Location: Placerville, CA USA Vehicle: '04 08 Tribeca, SVX Gold, Maroon	No, it did not. Legacy, up through 1994 did not have EGR. Impreza from 1993 to 1998 has EGR; Legacy from 1995 through 1998 (2.2L) has EGR; Legacy, Forester, Impreza w/2.5L twin cam has EGR.

07-06-2001, 05:44 PM	#16
skidplatez Scooby Specialist Member#: 1575 Join Date: Jun 2000 Location: Atlanta GA, USA Vehicle: 2000 RS BRP Cobb, DMS, Stromung, Whiteline	Besides Blindeye_03, it's illegal is STS.

07-06-2001, 06:32 PM	#17
Blindeye_03 Scooby Guru Member#: 4418 Join Date: Feb 2001 Chapter/Region: South East Location: Eastman, Ga. (aka Armpit Ga) Vehicle: 03 Silver Civic Si 05 Suzuki SV650	Well thats good to know . 1) it was just a question 2) I cant disconnect the EGR valve even if I wanted to, b/c MY01 impreaza's dont have it... BTW...I need to get a SCCA solo2 rulebook...