Thread: People with No EGR's - Question for all of you

Alright after you have removed your EGR, did your gas mileage go up or down? Performance probably stayed the same, but let me know if it went up or down.

Thanks guys

I didn't notice any difference, but I also did the entire header-back at the same time. The main benefit to removing the EGR crud is cleaning out all the gunk that collects in the system from it.

The more I think about this question, the more I think it becomes impossible to know haha.

The effect the recirculated exhaust gas has on your engine depends on whether that particular gas was the result of a rich or a lean engine cycle...

So, the recirculated gas was from a rich cycle, you would still run another rich cycle due to the extra added fuel but lack of oxygen in the exhaust gas. If it was from a lean cycle, you would run closer to normal, since the exhaust gas would be more representative of normal air.

However, you also have to take into account the fact that your 02 sensor is constantly helping to adjust your mixture based on the same results.

I think it's too complicated to accurately predict, but my best guess is that your mileage should increase after removing it as there will be no more error by your intake system metering exhaust gas as normal air.

I also think the effect would be too small to notice

Good observations Danja. And very valid points haha

Well I've tried searching the interwebs to find any info about it.

Now here are my thoughts on it.

The Good:
1. No exhaust gases going back into the your TB - We all know that we have to clean our TB's with some carb cleaner and tooth brushes once a year because of the gunk build up. The build up is known to decrease performance and MPG's.

So no EGR means non of that mess that you then don't have to worry about cleaning.

2. Clean, colder air gets into your engine thus should get a better burn. So possibly more performance, cleaner plugs, better mpgs.


The Bad:
1. More pollutants
2. Could decrease MPG's (not sure how but read on the web)
3. Could make the engine overheat (not sure how but read on the web)

I think with the overheating issue, it's caused by air substituting the exhaust gas that would have been recirculated, creating a leaner mixture and higher combustion temps... damn. I just realized that point is moot because of the O2 sensors. Nevermind, pass.

Both very true, removing EGR will certainly clean things up for your engine.. not the environment of course

And of course that could mean your decent MPG's will last longer due to the cleaner nature of plugs for a prolonged period of time. That is definitely a good point there.



I don't know about that one.. seems fishy.. the replacement of recirculated gases with normal air would improve the efficiency of the engine. More and better combustion = naturally more heat, but there's no way it's going to be enough to overheat literally.

Wow. You got some good responses Vadim!

Haha thanks Tommy

So my main reason for killing the EGR, I hate the Header bolt

LOL just make sure your replacement bolt doesn't fall out while driving like mine... after searching everywhere for a f*cking replacement of some sort I had to give up and get it welded at a shop.

I was thinking about this and since EGR doesnt really work at wide open power output would be the same. But when EGR recirculates back into intake the dirty air has been burnt once and could not efficiently burn again. So since we now have more clean air in cc we can also add more fuel and run at stoich. Which should help out part throttle driving. EGR was designed to help reduce NOx by reducing combustion chamber temps. Please someone correct me if I am wrong but fuel mileage should be almost the same but maybe better throttle response at part throttle.