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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 :D.

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 :D.
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...