I was staring off into space one boring auto class and though, if up to 14% exhuast gas is being recirculated... why not just unplug the vacuum line from the EGR, no more exhuast gas, would take a bit for the engine computer to compensate, and your check engine light would come on (theres a sensor on the EGR, might be tricky to get rid of it.)

Only downside i see in it is the possibility of detonation from the increased combustion chamber temps...

Or is this already a mod people do in non emmisions states?

man, that sucks that your auto class is boring

meh, you could do it. Doubt you would see much of an improvement though.

You could always put it on a switch though

The only reason it was boring is it was in the classroom talking about emmisions controls... and how they rob us of power lol... ive prettymuch outgrown highschool auto and know everything they will teach us. The only time i work on a car is when its my own, any other car and im not motivated to work on it (seeing as most cars that come in are pieces of crap)

c'mon it's earth day..LOL

lol, c'mon, its not like its going to make black smoke come billowing out your exhaust, its just burning more fuel/air, at a higher temp mind you... but i would look at it like more complete combustion haha

hahahaha @ Danny

Study up for some SAE tests then
I was in your shoes too, except my shop teacher just let me go work on my car or on teachers cars while the rest of the class had to do a lesson (normally because I could pass the chapter tests with out opening the book, hah).

Man I miss shop it was so much fun, lol.


Also was your teacher telling you that the emissions stuff was robbing power? In reality a majority of the emissions equipment really does not rob a substancial ammount of power at all. Infact alot of the time (with maxima's atleast) you can barely feel the gains, and if you weren't looking for them, you probably wouldn't notice them. IMHO, the smog equipment got a bad wrap because it was introduced at the same time as emission control laws were. The smog equipment alone wasn't the only thing that changed. The cars came with milder cams from the factory and intake/exhaust changes were made, its just that no one paid attention to that aspect.

If you disable your EGR your NOx shoot through the roof. My EGR was malfunctioning, and after I fixed it I noticed no apparent decrease in performance. [Hippie rant] Do you want your grandkids' faces to melt when it rains out? Keep the EGR valve functional, unless you are at the track. [/Hippie rant]

He didnt say anything about robbing power, i just assumed that putting a fair bit of exhaust back into the intake couldent be too good power wise.

it's basically putting 'dead air' back into the intake to be combusted. It keeps combustion chamber temps down like Mizeree_X was saying.

Dead air that once compensated for would be replaced with air/fuel, but the more i think about it, the more im not inclined to do it, higher combustion temps=deto=retarded timing=less power=oh well, worth a shot right?

might as well give it a try.
I was saying earlier, you might want to put it on a switch inside the car, so then you can do a pull or two, then flip a switch. Just makes it easier to feel the difference.

Heck I didn't even really notice a difference between having the VTC's grounded and not grounded until I had the switch there. wooweee what a difference.

The problem with a switch is, its not electrical, its vacuum operated, unplug the vacuum line and block it off, it takes the computer time to compensate for it (doesent it?) the only sensor that could notice it (that deals with the fuel delivery is the O2 sensor, and even then i dont know if it could make a big enough difference to fully compensate for it. The only way to remove it, or well trick the computer into thinking its still working (ie, keep the check engine light off) would be to disconnect the tube that comes off the manifold and block both ends off.... now that i think of it you could re route the tube into the intake again again behind the MAF (so it senses the extra air) and it should add the requred fuel?

BTW, this is on a 94 GXE... i know it will never be as cool as an SE lol

I don't know how the EGR is controlled on the GXE, but on my SE the vacuum source going to the EGR-C solenoid was bad. I had no check engine light. Disconnect the vacuum line going to the EGR-C, plug it up and the EGR shouldn't open and you shouldn't get an error. But like I said, please don't run it like that all the time -- all that pollution isn't worth the negligible gains (IMHO). Also, the exhaust gas going into the intake is weak in oxygen and healthy in inerts (which is how the exhaust gas cools the combustion temp), so re-routing the exhaust to pass through the MAF probably won't do much.

i didnt mean passing exhuast through the maf, i meant taking that tube out, blocking it off on the manifold (so no exhuast comes out the now empty hole) and make a tube that connects to the intake manifold (on the plastic part for ease) so that instead of letting exhuast gasses through the EGR valve, its sucking fresh air into it, and scince that air is accounted for by the MAF, it should be compensated for... no?

there is an EGR temp sensor
also, there is an EGRC Solenoid Valve actuated by a ground signal from the ECU

more info about it in the FSM

When I had my E-test, the Nox was through the roof. It didn't throw any codes, but I took off my EGR, cleaned and lubed the valve and put it back on. Passed with flying colours. She bareky registered in all three categories. I noticed that the car actually ran better too. I'd leave it alone.

i think only the california models got the EGR temp sensor

my car has the plug for it in the harness but no sensor although you can see the inprint in the intake manifold where it would go

When I was diagnosing my EGR, I got all worked up because I couldn't find the EGR temp sensor anywhere, then I finally realized that I didn't have one.

Some thoughts:
a) Since the EGR only works for part throttle, it really doens't affect performance in any measurable amount.
b) The statement that emission controls "hurt" power is an interesting statement. In the late 70's - late 80's, I would say that's true. But emission requirement spawned modern fuel injection and computer based engine management as we know it now. These technologies allow engines to run more hp, less emissions and greater mpg all at the same time. Not to metion the benefits of engine longevity due to a cleaner running engine.
Jeff92se's lesson of today. Sorry to bring you into class again.