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Discussion Starter #1 (Edited)
What is the EGR system and what does it do?
http://en.wikipedia.org/wiki/Exhaust_gas_recirculation said:
Exhaust gas recirculation (EGR) is a NOx emissions reduction technique used in most gasoline and diesel engines.

EGR works by recirculating a portion of an engine's exhaust gas back to the engine cylinders. Intermixing the incoming air with recirculated exhaust gas dilutes the mix with inert gas, lowering the adiabatic flame temperature and (in diesel engines) reducing the amount of excess oxygen. The exhaust gas also increases the specific heat capacity of the mix lowering the peak combustion temperature. Because NOx formation progresses much faster at high temperatures, EGR serves to limit the generation of NOx. NOx is primarily formed when a mix of nitrogen and oxygen is subjected to high temperatures.
Why might you want to remove the EGR system?

1) Your EGR valve is malfunctioning and you'd rather not spend the money to replace it.
2) You are installing a turbocharger and do not want to go through the hassle of connecting the EGR pipe to your turbo manifold or downpipe (this is the reason I removed it).

Note: You will not see any performance gains by removing this system, and here's why:

Nissan Altima Factory Service Manual said:
When the ECM detects any of the following conditions, current flows through the solenoid valve. This causes the port vacuum to be discharged into the atmosphere. The EGR valve and EVAP canister remain closed.
  • Low engine coolant temperature
  • Engine starting
  • High-speed engine operation
  • Engine idling
  • Excessively high engine coolant temperature
  • Mass air flow sensor malfunction
This likely means that at wide-open throttle, i.e. when you're trying to go fast, the EGR valve remains closed.

Section I - Disabling the EGR system without removing EGR components (without turning on the Check Engine Light)

Materials needed:
  • Something to plug a vacuum line - I used a bolt, but a golf tee would probably work, or you could buy a vacuum line plug/cap if you feel the need
  • 68k ohm resistor - I used a 1/4 watt resistor but I imagine a 1/8 watt or 1/2 watt resistor will work just fine
  • Electrical tape
First, locate the EGR valve on the intake manifold, near the back of the engine bay. You need to pull and plug the vacuum line going to it (circled in red), which will stop the EGR valve from opening. If you plan on removing the EGR system components, you should pull and plug the hose circled in blue instead, or alternatively, you could pull the hose circled in yellow (kinda hard to see) and cap the metal t-fitting that that is plugged into. These hoses are connected to the EGR-BPT valve, which you should be able to safely remove as long as the EGR valve is removed as well. (I'll confirm this when I attempt to remove it)



The next step is to ensure that the Check Engine Light does not come on. Locate the harness for the EGR Temp Sensor. It can be found a few inches above the back side of the throttle body (circled in green). Disconnect the harness, and insert the resistor into the bottom half, which is the half that is wired into the ECU. Make sure you get the ends of the resister properly inserted into the harness, and push it in as far as you can. This will ensure a solid connection and also decrease the likelihood that it will fall out. For safe measure, I then covered this half of the harness with a piece of electrical tape to make sure the resistor stays in place. As you can see, I took this picture after I had already done it, so I simply pulled the tape back to take the picture. You can just leave the top half of the harness hanging there - this connects to the EGR Temp Sensor, which you can just leave bolted into the intake manifold since it isn't doing anything anymore (unless you want to remove that as well, in which case you will need a bolt of the proper size to plug the hole in the intake manifold).



If all you wanted to do was to disable the EGR system, you are now done. However, if your EGR valve is stuck open, or if you installed a turbocharger and your EGR pipe is not connected anywhere in the exhaust stream, you need to do something else. You could buy an EGR Plug/Fitting - part number TK266 from jgsturbo.com - and use it to cap the end of the EGR pipe that is normally connected to the exhaust manifold. This will stop the flow of exhaust gas from even getting to the EGR valve. However, if you're like me and you hate things being there that serve no purpose, continue on to the next section.

Section II - Removal of the EGR components - I will update this part when I actually do it in a few weeks

Materials needed:
  • A set of block-off plates - I got mine from Ace for $20 shipped, or you can make them yourself
  • New gaskets for good measure - Nissan Part #'s 14719-W0402 and 14720-1E410 (cost me $12 for both at my local dealership)


more to come...

Sorry if I dumbed this down a little too much for most of you - I wanted to make sure that absolutely everyone who reads this understands how and why it is done. Thanks go out to jserrano, Ace, and Ben at Jim Wolf Technologies for their help in getting this figured out.
 

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badass man, thanks. I have to do this for my intake manifold install :)
 

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Discussion Starter #3
no problem! if you're installing the xcessive manifold, then you'll only need to buy the second gasket part # (the one on the right in the pic), and you'll only need to buy/make the block-off plate for the same part, not both.
 

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hey bud. sorry just a quick question...sorry if this is a dumb one, but...the resistor.. do i plug both ends in? one to positive, one to negative? do i loop them both into positive? or whats up? i can't really tell by the pics. thanks.
 

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Discussion Starter #7
np. if you end up doing it, post back your results after a couple weeks (i.e. whether or not the CEL actually stayed off). i had an issue a while back where the light came on, but i think the resistor just came loose.
 

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sounds good, this actually fixed the problems that i was having, i would rev and it would just bog and die. i guess the EGR valve just worked as a big vacuum leak.



i just finished making my plates today, i'll let you know how the resistor goes and what not..just have to throw my koyo rad , and header in once they get here...hopefully some day soon....lol :crazy:
 

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Twizted Innovations C.C.
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Are the steps the same for a 2nd gen? I've really been wanting to get rid of my EGR and this is a great step by step break down.
 

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Discussion Starter #12
np chuck.

the steps should be the same. i say should because i think the emissions system may have changed a little bit on 00-01 models. however, i do believe that the EGR system is the same so this thread should still apply. sorry i cant be more certain.
 

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Rippen RJ
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Good stuff Zadeluca, I'm going to have to do this pretty soon for the turbo. Unfortunatly I can't remove it all off cause I gotta smog again.. gotta love Cali..
 

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Discussion Starter #14 (Edited)
awesome. then what you need is an EGR Plug/Fitting - part number TK266 from jgsturbo.com. you can use it to cap the end of the EGR pipe without removing it.

honestly though now that i think about it, you might not even need that. as long as you use the resistor, the EGR valve should never open, so theres no real need to worry about whether or not the pipe is open or not. EDIT: this is assuming your valve is not stuck open, then you will not have a vacuum leak.

what are you gonna do when you go for smog? remove the turbo completely?
 

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Rippen RJ
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awesome. then what you need is an EGR Plug/Fitting - part number TK266 from jgsturbo.com. you can use it to cap the end of the EGR pipe without removing it.

honestly though now that i think about it, you might not even need that. as long as you use the resistor, the EGR valve should never open, so theres no real need to worry about whether or not the pipe is open or not. EDIT: this is assuming your valve is not stuck open, then you will not have a vacuum leak.

what are you gonna do when you go for smog? remove the turbo completely?
That's what I thought to, but I might buy the cap just in case. But yeah when I smog I do plan to remove it completely :banghead::banghead: Don't know anyone who would just pass smog in San Jose, Cali would ya haha... Nah but my brother said it won't be that bad, he had to remove his things when he had to pass his DSM. Went from 500hp to barely 200hp for smog hahaha
 

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does anyone know the size of fastener i would need to blockoff the egr bung in the header? thanks a million.
 

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Warmachine.. i can probably hook you up with a smog hook up.. I know someone that you can send your info for smog to in LA and he will do w/e he does and your car will "pass" smog.. but its around $200 for the smog if your interested...
 

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wanting to go get a bolt to plug my egr port in my manifold...
can't get my old one out...
does annnnyyyone know the size? lol :confused2
 
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