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Thread: EGR Delete information

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Posts: 1-10 of 21
2009-11-09 18:42:31
#1
EGR Delete information
It seems this question is asked WAY too often, so I thought I would compile what information I am aware of to make it easier to find the info a person is looking for in regards to deleting their egr system, reattaching it, upgrading header, rerouting vaccum lines, etc.

Nissan's plug:

nissan part number 14052-21R00

called a 'plug taper'



Nissport's plug kit along with blockoff plates
highport: NISsport EGR Blockoff Kit with Gaskets for High Port SR20DE
lowport: NISsport EGR Blockoff Kit with Gaskets for Low Port SR20DE

Information on EGR Delete:
Leaving EGR open?? - SR20 Forum

OBD2 egr delete info *MAKE SURE YOU READ THE WHOLE THREAD, THE INITIAL INFO IS INCORRECT, AND IS FIXED LATER ON IN THE THREAD*
SR20 EGR Removal thread - B15 Sentra Forum - Nissan Sentra Forum
Need Help with 100k ohm resistor for EGR? - SR20 Forum

Highport vaccum hose rerouting for deleting EGR

Thanks to Llprad's info from the other forum:

From the Haynes manual for reference on the corresponding numbered hoses:



Here's what you have in stock form:

... the "triangles" are where 3 hoses join each other via 3-way or through the gallery.

FYI, the "gallery" is the metal hoses all buched up together, connected to the BPT valve and the EGR tube,

Here's AFTER you've discarded, what to rehook and add:


Ive done it this way, and everything runs swell! Although now I have to turn the idle down a notch.


Line rerouting for lowport:
Original


Original


How to delete the egr without removing stuff (visual inspection approved )

"Dont bother with a block off kit. There is a hose going from the BPT to the EGR, just pull that off and plug it up on the BPT side. That will stop the EGR from opening and sucking air in through the pipe. You can just use a screw to do it.


The one with the two lines going to it is the BPT which is what regulates the EGR. One of the tubes normally connects to the EGR, but as you see I disconnected the tube From The EGR and plugged it, leaving the EGR side open. Doing this basically stops the EGR from opening and drawing in any exhaust gasses... a very smart thing to do if you dont have the tube connected to the header.


How to reattach egr pipe when upgrading or replacing header:
Make sure when you put the exhaust manifold back on to NOT bolt it on first, attach the egr tube first, THEN bolt it to the head. The EGR tube is bent slightly and WILL NOT attach easily if you install to head first. The bolt size is an oddball one, most use Visegrips to take it off because of this:
Originally Posted by canx2k
The item I'm speaking of is the pipe that comes off exhaust port #4. The size of it befuddles me.

I for the life of me can't figure this out. 7/8" is too small.
15/16" is too big.

22mm is too small
24mm is too big!

Is it just me or is this the dumbest thing ever made. I need a 29/32" or a 23mm wrench?! That's F'd. I tried a crescent wrench, and there isn't enough space to take it off. The same goes for the long tube at the bottom, below the o2 sensor spot. How am I supposed to get that *ish off there!?!


Does removing the EGR effect anything? According to this thread and a reputable member on the forum:
http://www.sr20-forum.com/all-motor/14574-any-advantages-without-egr.html
Originally Posted by Andreas
The only pro to removing the EGR is making the engine bay look cleaner.


With or without the EGR the car will make the same HP under full throttle.

The EGR only comes into play under normal cruising condition.


Also worth mentioning:
Originally Posted by BRE92SER
no, it wont effect Air/fuel ratio, and it wont make the cat's life shorter. its sole purpose is to lower NOx by reducing combustion chamber temperatures by taking up physical space in the cylinder, meaning there is less burnable mixture in it (exhaust doesnt burn), therefore reducing the energy produced per cycle. by lower temperatures, we reduce NOx emmisions, which are produced when combustion temperatures get too high and begin oxidizing(burning) the near-inert nitrogen gas in the intake air. also, it doesnt shut off at mid-throttle, it's OPEN from light throttle (around 15% i think) to around 70% throttle. (Fedral emmsions standards dont currently take into account any values over 70% throttle opening). its closed at idle, otherwise the engine would idle poorly, if at all (hook a vacuum pump up to the valve at idle, you'll see what I mean), and it has a major effect on power, so its not open when power is demanded (70% - wide open throttle).





tags: egr delete plug aiv ssac header bung plate vaccum reroute line bpt valve
Last edited by BenFenner on 2020-06-12 at 18-13-00. Reason: Update two image URLs since the non-dash forum has lost the originals.
2009-11-09 19:07:32
#2
Cleaning EGR and BPT information taken from se-r.net:

PROBLEM: Surge and hesitation between 1500 and 3000 rpm

Affects: All '91 - '93 SR20DE (Sentra SE-R, NX2000 and G20)


Red arrow: EGR valve
Yellow arrow: BPT valve

Green: BPT valve
Red: rubber tube
Yellow: End of metal tube
Orange: tube routing
If the usual tune-up procedure doesn't take care of the problem, disconnect the EGR valve and plug the vacuum hose leading to it from the BPT valve. Take the car out for a ride, making sure to drive in the same manner that typically causes the car to surge and hesitate. If the problem is no longer present, chances are good that you're experiencing the infamous "EGR Problem".

Remove both vacuum hoses from BPT (right-most disk shaped object behind valve cover). Remove the two philips screws on its top. Push the BPT back toward the firewall. You should see a rubber hose running between the bottom of the BPT and a metal tube. Remove the BPT and rubber hose from the metal tube and set them aside.

This metal tube is connected to the EGR passage and, ultimately, to the exhaust manifold. Exhaust manifold pressure, via this metal tube, operates the BPT valve which regulates the vacuum to, and the opening of, the EGR valve. The less exhaust manifold pressure - the more the BPT valve opens - the more the EGR valve opens. The more exhaust manifold pressure - the less the BPT valve opens - the less the EGR valve opens. Carbon may block this metal tube which causes the BPT to not operate properly (if at all) which causes the EGR valve to operate uncontrollably.

Wait until the car is cold, then spray some carb and choke cleaner into the metal tube to soften up the blockage. Used a stiff piece of wire (a long chunk of 8 gauge wire left over from the big car stereo install will do) to ream out the tube. (*Note: DO THIS WHEN THE CAR IS COLD!! Carb cleaner and a hot exhaust don't mix well.*) Take note of how far you have pushed the wire into the tube before you pull it out. Lay the wire along side the BPT tube to gauge how far down the tube you have gone. When you've pushed the wire far enough down the tube to have reached the EGR tube it intersects, you've probably removed all of the blockage(s)

Wait about 10 minutes for the chemicals to evaporate. Start the car and hold your finger in front of the metal tube. You should feel a steady stream of exhaust coming from it. If not, try cleaning it again.

While you're waiting for the chemicals to evaporate, now would be a good time to remove your EGR valve and clean the carbon deposits from the plunger and seat. I find that the carbon build up eventually gets bad enough to hold the EGR valve slightly open. This changes your base idle speed (TPS disconnected) and can also cause a rough and wandering idle as well as possibly causing your car to stall when you push in the clutch.

Reassemble the system, hook your EGR valve back up and take your car out for a ride. You should find that the problem is gone and your local smog police will give you an award for being a law-abiding smog free citizen once more.

I make checking the metal tube and cleaning the EGR valve a part of every tune-up and/or oil change.

Images found here:
Engine bay
BPT tube

Little more b14 specific info here:
Originally Posted by DC
Here's how I clean the EGR components.

Purchase both EGR gasket and a can of throttle body cleaner (Valvoline SynPower works great).

The EGR has 2 parts: EGR valve & EGR base. Both holds carbon buildup and should be cleaned. I normally clean both but I've seen people only clean the valve. When doing both, you must purchase both gaskets.

- Remove the EGR valve and sit on a flat surface with the inside part facing up.
- Fill the cavity with the cleaner, push on the round part to open & close the valve.
- Pour out & refill, then let soak in cleaner for about an hour. Repeat until clean. Using a small brushing helps on stubborn buildup areas.
- The goal is to remove the carbon build up; especially around the valve seat.
Note: its better to let the carbon dissolve in the cleaner; brushing it while dry gets tiny carbon chips everywhere & makes the job much harder..

- If you removed the EGR base section, simply soak it in a small container (1lb coffee can) with throttle body cleaner. Brush the inside with a old toothbrush and let soak again for an hour. Wipe clean & reinstall with new gasket.

- Reinstall EGR valve with new gasket.

This procedure also works great for the IACV/AAC unit.
2009-11-10 06:20:38
#3
Nice write up.
2010-07-22 20:39:33
#4
....I searched for this thread for 20 minutes.....again!!! It was right under my nose.
2010-07-22 20:45:49
#5
When did this get posted?
Great job canx2k. I think you should add that with EGR removed you're likely to get slightly worse fuel economy. I could get into why, but it's not there just for emissions. It's there for fuel efficiency too. It does this by removing a lot of the pumping losses during partial throttle.
2010-07-27 18:58:55
#6
Originally Posted by BenFenner
When did this get posted?
Great job canx2k. I think you should add that with EGR removed you're likely to get slightly worse fuel economy. I could get into why, but it's not there just for emissions. It's there for fuel efficiency too. It does this by removing a lot of the pumping losses during partial throttle.


Please explain Mr fenner.
2010-07-27 19:21:43
#7
The vacuum created in the intake manifold takes energy to create and specifically is a drain on the engine. The reciprocating drive train has to work against itself for every intake stroke. If the engine is idling or you're cruising around at small throttle openings then the engine is effectively breathing through a tiny straw, and that's hard work, and it creates a lot of vacuum. All else being equal, if you open the throttle all the way the engine wouldn't have to do as much work and would suffer from a lot less parasitic pumping loss. However, opening the throttle presents it's own problems because you'll get more air and then you'll get more fuel and that's not good for economy and maybe you don't want to accelerate at WOT everywhere you go.

If only there were a way of letting the engine "breath" some inert gas that would eliminate or lessen the pumping losses and wouldn't affect the air/fuel ratio at all. Like a separate tube hooked up to a never ending tank of argon or something.
Well guess what? Exhaust gas is inert, so EGR systems are designed to feed exhaust gas into the intake manifold at these times to help lessen pumping losses.
Bam! Instant fuel efficiency increase. Similar to turning off the A/C compressor or other mechanical, parasitic devices.
2011-09-21 03:18:02
#8
Bump for Blair so he can delete his charcoal canister.
2011-09-21 18:39:42
#9
Great write up! I finally got my header on and exhaust done, this was my final issue. Now I know what to route where...

Lots of info, I like it! Thanks
2011-12-27 19:31:03
#10
Has anyone followed llaprad's diagrams and been successful????? I am about to do this even though there is an easier way!
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