Code 71, Egr Problems? Read This!
I'm resurrecting this thread and looking for some answers to questions about EGR systems in general.
I have also just gotten the CEL for the evil Code 71. This troubleshooting guide is fabulous if you can take the time to fix it, but as to consequences of NOT fixing it are what I'd like to ask some of our knowledgable members here.
What happens if you don't fix the EGR when the valve is stuck open/closed? What are the consequences? Bad gas mileage? Something worse?
What does 94GS300 mean when he says there is a better chance of 'pinging' under load?
What are the pros and cons of EGR block off plates? What other methods are there in dealing with the CEL itself or the problem of it reading off EGR values?
I have a boost gauge set up and its been reading odd vacuum values in the manifold for not too long before the CEL came on. Is this an indication of an EGR issue? If so could you explain why?
Answers to one or all would be greatly appreciated
I have also just gotten the CEL for the evil Code 71. This troubleshooting guide is fabulous if you can take the time to fix it, but as to consequences of NOT fixing it are what I'd like to ask some of our knowledgable members here.
What happens if you don't fix the EGR when the valve is stuck open/closed? What are the consequences? Bad gas mileage? Something worse?
What does 94GS300 mean when he says there is a better chance of 'pinging' under load?
What are the pros and cons of EGR block off plates? What other methods are there in dealing with the CEL itself or the problem of it reading off EGR values?
I have a boost gauge set up and its been reading odd vacuum values in the manifold for not too long before the CEL came on. Is this an indication of an EGR issue? If so could you explain why?
Answers to one or all would be greatly appreciated
Advanced
Joined: Aug 2007
Posts: 684
Likes: 3
From: CO
Not sure what the repercussions are but for NA-t probably be best to delete the EGR since you don't want exhaust gas to recirculate but that will depend on your state's emission laws. You could also take out the modulator to clean up...I've got fed up with it and put a resistor in the temp sensor so the check engine wouldn't go on. i didn't remove anything, just added the resistor. Been fine...same gas mileage as before which is 20-25mpg. good luck
Not sure what the repercussions are but for NA-t probably be best to delete the EGR since you don't want exhaust gas to recirculate but that will depend on your state's emission laws. You could also take out the modulator to clean up...I've got fed up with it and put a resistor in the temp sensor so the check engine wouldn't go on. i didn't remove anything, just added the resistor. Been fine...same gas mileage as before which is 20-25mpg. good luck
Advanced
Joined: Aug 2007
Posts: 684
Likes: 3
From: CO
I think it was 1 dollar total.....I forget the specifics for the ohms but if you search egr delete on here you can find it. I'll see if I can find the exact for you. Not sure if obd1 and obd2 is any different regarding the resistor though.... here https://www.clublexus.com/forums/per...f-off-diy.html same procedure....buy it at radioshack. I didn't know what I was doing at first...but if you find where your egr is and follow a connector by the temp sensor you will eventually see a plug...put the resistor in, secure it and you are good to go.
Last edited by bangdangvn; Sep 17, 2009 at 04:05 AM.
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Driver School Candidate
Joined: Dec 2009
Posts: 1
Likes: 0
From: california
my 94 gs (184k miles) needs work-
hi everyone -not sure if anyone can help with this----i recently moved and i am in need of a honest, reliable-mechanic to maintain my 1994 gs im in the canoga park area (san fernando valley) either mobile or a shop, im really busy and moved to an apartment building were "tinkering" is not alowed-- so please if anyone can help a fellow gs lover out it would be appreciated!--thank you if this post is in the wrong place please direct me in the right direction thank you.
Driver School Candidate
Joined: Mar 2010
Posts: 1
Likes: 0
From: WA
EGR pipe capped
91 LS400. 200k. car is a Jewel, owned it for 10 years now and plan on keeping it for another 10. Had a cracked EGR pipe and decided to have it capped off. Car runs like new with exception of CEL & code 71, traction off light on. Reset the system, at higher speeds the CEL & Traction off comes back on. Have a hunch it's the capped pipe that's at the root of the problem as prior to capping there was no CEL code 71, coincidence or perhaps not.... Would EGR block off plates make this go away?
Without the assistance of this forum there is no way I'd be able to keep this machine running like a top. A big Thank's to all of you trouble shooters out there, taking the time to respond to what must seem trivial stuff at times I am sure.
Without the assistance of this forum there is no way I'd be able to keep this machine running like a top. A big Thank's to all of you trouble shooters out there, taking the time to respond to what must seem trivial stuff at times I am sure.
EGR Modulator
just fixed my check engine light that has been on for a month, all thanks to this tread.... for my prob, i replaced my egr modulator and replaces all the hoses to the egr modulator and egr valve, light has been off for 3 days now...
thanks to 94GS300, for doing this write up, saved me some money by doing it myself...
thanks to 94GS300, for doing this write up, saved me some money by doing it myself...
Driver School Candidate
Joined: May 2012
Posts: 1
Likes: 0
fu&*$n code 71
hey guys i just read this and it gives a lot of awesome info...ive got a 94 sc400 that has the same code. car runs good but without the light off it wont pass emissions test. does the same thing apply to my car as the procedures here? the fuel cap does hiss like a snake when it is removed. i love this car but im getting to the point to decide whether i want a monster truck to drive over it or not. 
Pole Position
Joined: Feb 2007
Posts: 208
Likes: 0
From: CA