EGR Blockoff Discussion [Merged 8-8]

[Puller]

Before I speak my piece, this is directed to 'tuners' who are some what new and are somewhat impressionable. However there are many of you that never learned certain things the correct way. This also applies to stock or nearly stock vehicles. That said: Although many DSM followers are on the forums to help and provide insight, many fail to understand how or why certain components operate in the way they do. Even on this site's 'tech articles' there are modifications which do far more harm than good. I'm only going to refer to the articles posted in the free mods of this sites tech articles. First i'll start with the EGR block off. Whomever wrote this deposition clearly had no idea what they were talking about. The purpose of an EGR valve is to recirculate exhaust gas into the intake, as many know. What people fail to realize is that the EGR valve was designed to combat knock. Exhaust gases, on a normal running engine, are inert. They are recirculated to COOL combustion chambers by displacing usable air with inert air. Coincidentally that acts as an emissions device by lowering NOX (which is a product of heat). NOX is the EPA's main concern as far as emissions. Another point, it's operative under light cruise, not under heavy accel or WOT because it's vacuum is from ported vacuum. So that doesn't even bother most DSM drivers ;-) So if you blocked off your EGR i have only a couple things to say: congratulations you just increased the likelyhood of knock and the emission of NOX. Also you just found a quick way to fail an emissions test. If people would stop and think, they'd realize they aren't as smart as the Mitsu engineers and the thousands if not millions of dollars of R&D that went into that "stupid emissions device". Another note: under WOT emissions isn't a concern. You're vehicle goes into open loop and runs rich. a rich mixture emits HC into the exhaust. therefor most emissions devices are disregarded during WOT including your O2 sensor.

 

[TheBoosted96GST]

hmmmm...the EGR valve doesn't have a harness?its not electrical, it only has 2 vac lines coming out of it right? i'm just asking...using a block off plate (gasket) but leaving the 2 vac. lines connected to the egr valve...will it cause any ill effects since the vac lines will still be connected from the TB to the EGR?

 

[absolute_DSM]

The vac lines go from the throttle body to the soleniod then to the EGR valve. Follow the lines and youll see what I mean.

I dont know how you think you can use a gasket to block off the EGR. I really dont see why youre trying to do this anyways.

 

[DSMunknown]

Yes, you can just install a EGR block-off plate and leave the EGR valve and vacuum lines intalled if you wish. Just follow my guide or the one on VFAQ and you'll be all set.

 

[TheBoosted96GST]

awesome, thanks for an answer, i know how to do an EGR block off, done it to several dsms in the past but never left the vac lines leading to it, i removed all vac lines and blocked of tb nipples in the past. 2nd question i'm going on a long trip here in the next few weeks about 800miles of highway driving, will the block off cause engine harm? i know this EGR topic has been discussed a billion times will all different opinions, maybe what i'm asking for is has anyone with the block off had problems during long highway trips?

 

[DSMunknown]

How could blocking off the EGR possibly do a lot of harm (if any) to the engine? The answer is, it won't. It's not even an essential part of engine performance. Stop worrying, you worry wort.

 

[tenn-gsx]

Ok not to thread jack but what if I dont put in block off plates, and just remove the vacume lines and cap them at the intake mani?

 

[BUCK]

Ok not to thread jack but what if I dont put in block off plates, and just remove the vacume lines and cap them at the intake mani?

The EGR Valve shuts & stays shut, no problem as long as you don't have State Emmision Tests.

 

[laserspeeddemon]

Thats not true, it becomes a potential boost leak.

 

[BUCK]

Personally I tapped the EGR Port in the Head & drove a Pipe Plug in it, FAR better than a Blank - I concur that indeed it's a potential "Boost Leak" - kinda sorta - as it would "leak" back into the Exhaust but the EGR Valve is "spring loaded" shut when no Vacuum is applied - If EGR is stuck open you have another mess - Plugs look like Charcoal Briquets~!

 

[91WhiteGSX80]

Hey hows it going guys... Now I been reading and reading about this EGR.. and I still cant decide i do want all that shit out of my engine bay cause im bout to put a new head on my car ..but then again i dont have that DSM Link thing to tune my car to pass emissions cause you know how New Jersey DMV is ... theres nuts the shit you cant have tint and exhaust and all that stuff but is there any other way i can tune my car so I can pass the emissions... and if so what do I have to do..?? thanks guys

 

[Menacing talon]

Why not just make it easy on yourself and buy a sticker?

 

[gijoe985]

Hey, can anyone give me their thoughts on the pros and cons of blocking the EGR?

I've seen defiant say that it is bad to do, which sparks my interest because it used to be a part of the stage 0 upgrade path article. Why is it no longer suggested? Did we find something new out?

What are the pros of having it? I've heard people give completely opposite testimonies. Better emissions or worse? Fuel mileage? Power?

Just curious... seems like people are all across the board...

 

[daren_p]

Thats depends on what you think of when you say better for emissions. For an awd (that doesn't have NOX testing), it will probably be better in the fact that the higher combustion temps should reduce CO & HC's. For a car that has to be tested for NOX, it will be much worse. Also for the environment, it will be worse.

As for gains, the only you will see is maybe a cleaner intake mani as you will no longer be recirculating exhaust gases. The won't be any "real" performance gains as the EGR is only open under certain cruise/light load conditions & therefore doesn't effect WOT performance.

 

[force_feed]

I've noticed worse gas mileage sense I blocked off mine.
No biggie

 

[BoostedinSoFla]

I have horrible gas mileage but I'm unsure if it's because mine is also blocked or if it's just cause I might be running pig rich. I do, however, have not had any ill effects from doing this with the exception to the "EGR Malfunction" CEL that pops up every now and again. And yes, all my sensors were left plugged in.

 

[crimsondragon]

If you have the money and are at that stage, you can get an intake manifold which can eliminate the the whole EGR and FIAV. With proper tuning you can have it run lean at idle making it burn hotter and thus imitating what the EGR does.