egr valve?

[kamikazestorm420]

what does the egr valve do?

and if it messes up does it affect any performance? or is it bad to run with the egr messed up?

[IveBeenBad]

the egr lets exhaust gasses into the intake, and the whole system can be removed...

[kamikazestorm420]

so it wont mess up my motor by drivin it with the egr messed up?

[IveBeenBad]

im not sure of the adverse effects, i know it wont ruin the motor though

[kamikazestorm420]

oh.

well my check engine light came on and i checked the code and it told me about the egr valve.

i heard that it affects emissions but if thats the ONLY thing it affects i dont want to spend the money to fix it/replcae it because i am going to do a sr20 swap soon.

[sonic16]

yes it is an emissions control system, It recirculateds exhaust gases so that they can be fully combusted.it can be removed but it will cause your car to produce higher emission levels.

[kamikazestorm420]

btw .. where is it located and how would i remove it?

[SilverSX95]

If you look at the exhaust header you'll see a copper pipe coming out of the top and around the back of the motor, then it goas to the EGR valve right on the back of the intake closest to the firewall. Hope that helps.

Matt

[gumby]

is the little pipe to the bpt removable ive unscrewd it but it wont come out. not sure if its fused with rust or what the thing is filthy. are they worth replacing or just cleaning.

[240sxJay]

Removing the EGR valve is a long and tedious process (2-3 hours). There are no hp gains, and it only has to deal with emissions. The only reason why I would see someone wants to remove this is so the engine looks cleaner/clears up *some* space. I had to deal with this ****ty valve when i installed my headers...i'm just going to weld that thing into my headers cuz it's a pain.

[Iwant240insteadofP/U]

Im not the most informed person about this stuff but I am learning I belive egr is exaust gas regulator. It brings exaust gasses into the intake to burn to lower the amount of gassoline that goes unburned and released into the atomosphere. If I am not mistaken this also serves to lower combustion temps and reduce risk of detonation(doesnt mean it will detonate without an egr but it is even less likely with your egr in tack). Also I belive I remeber my teacher mentioning that gassoline particles caught in the cat can cause it to burn out faster(again I dont think its a huge problem just more then with egr inplace) Again I am no expert and it would be nice for some one to back me up or correct me...

[Ubernoober]

Its purpose is to simply let exaust recirculate into the intake. The reason being that the exaust will displace some of the incoming air, reducing the oxygen charge. The computer then lowers the fuel delivered to match the amount of gas recirculated. In the combustion chamber, the lower fuel and air deliver less power, but burn slower (and slightly cooler) due to the increased ratio of non-combustible gasses. This will reduce the NOx significantly. The loss of power is only at cruise. In no way does this rob your car of power for acceleration. It DOES tend to coke up over time and dirty up the inside of your intake and of course also take up space in the engine bay.A faulty valve could cause your car to run lean during cruise when the computer thinks it is supposed to be open.

[wangless]

so this could also contribute to bad gas milage ?

[MrIllegalX]

I only put it on my sr20 to pass emissions, I take it right off afterwards. It doesn't cause any issues for me at all. They just look at it to see if its there...

[sonic16]

how the hell did you put that on your sr? that plug on the turbo elbow is there because the egr pipe doesnt clear the steering column. also why the hell did you go through the trouble as many of us arizonians have easily passed without it?

[Ubernoober]

EGR can have an effect on gas mileage, but it would be very small. In some cases positive, and in some negative. Overall, the thing is that if you remove it without re-tuning the computer, it will expect it to be opening and closing causing a small (very small) amount of confusion for the computer. Its not a big deal either way, but less pollution is always better when it doesn't affect your mileage/power. Leave it unless you absolutely MUST yank it.

As a side note, newer cars don't even have these since the combustion chamber design, fuel computer tuning and 3-way cats eliminate the NOx problem altogether. I wouldn't be surprised if you could run cleaner by stripping it off, re-tuning the ECU and throwing a good (though pricey) 3-way cat on. Sadly, smog rules don't take this into account and will fail you on a visual..... stupid smog laws.

[gumby]

well whats the proper way to service the egr? after 10yrs+ the inside looks like a rusty sewage pipe. i have a spare. ive grinded it out run 1/4 can a carbcleaner through it and scrubbed the pipe out. the one on the good engine is covered and fused with rust. i had to saw it off. it was working but if the other is any gauge its all rusted up inside as well.

will the car pass NJ emissions without it? will a garage pass it? can octane booster be added to compensate for the higher temps and prevent pinging?

[s13sr20chris]

egr can make your car run bad and lose power if it sticks open. sucks when that happens. nissan did away with egr for a few years and has now gone back because the old egr valve works better than the valve timing they were using to control nox.

[un_known]

Removing the EGR isn't exactly a bad thing or a good thing. But it may cause a little smoke from the exhaust because with out it your engine with burn a little rich.

[s13sr20chris]

really lack of egr should not cause it to run too lean or rich. the maf will account for any difference in airflow. you could get a little preignition at light accel.

[fatboy]

so this could also contribute to bad gas milage ?

yes

[gumby]

can you pass emissions without it (NJ) by adding octane booster? will a garage pass it? im installing an old one but if it ever gives me trouble id like the option to terminate.

[bentsprocket]

I didn't read all of this but the EGR only works while moving down the road and letting off the gas then it recycles SMALL amounts of exhaust. On inspections here in NC which I am an Inspector btw they look to see if it's there and connected. It will not effect anything for hp gains or loses. As far as for readings from the "sniffer" placed up your tail pipe. SR's don't pass here unless it's illegal they are not emission compliant and that's brave of the Inspector. Anyways, I love 240sx's but don't come to me I won't pass it. I got a family to support and a job to hold on to. Hope this helps

[s13sr20chris]

if you want to watch the egr operation while your driving do the following...break out the multimeterhook it up (pos) to egr temp sensor signal and (neg) to groundwatch voltagewhen egr is shut voltage will be highwhen it opens it will drop after its been open for like 2 mins on the highway or something you will get voltage down to like .02vthat is about the minimumstarting voltage will be like 2v or something

you will see that it operates at cruise somewhat and moreso on light acceleration. because of the bpt, there must be manifold vacuum and also backpressure from the exhaust.

[bentsprocket]

s13sr20chris, That's the more technical way but's that's great. I hope you'd agree to learn about something before you remove it or block it off. When you know it's purpose and function it's easy to work with.

to everyone else, however OBD1 and 2 differ (only small amount).

Off topic sorta on I read somewhere else "tell the Inspector it's a 2.0 and that will lower the values". This is not true!! When selecting the Make\Model..... on the machine and with the 240sx it knows there were only one powerplant no other's options to pick from. Trust me it's not that easy to fool the Gov. on emissions.

[gumby]

well unbelievably the rusted one was in better shape than the other. grinded out the rust with a dremel. ran way too much carb cleaner through it. naval jellied the outside $2 gasket good as new. well sorta. at least i had a spare pipe. wee!