This would be the fourth post I've ever posted on this forum about EGR deletes. If you read a lot of the posts on here about EGRs, people delete them because they have codes and they get tired of chasing codes. Well, the codes are there for a reason. Usually because of a blockage of some sort. They don't just appear out of nowhere. That could be because the engine isn't tuned right for a bunch of reasons. Instead of figuring out why that's happening, people here just remove the system altogether. A fully functioning EGR system does not hamper engine performance in any way. It may even *gasp* increase it.
If we were talking about a late 70s OPEC era emissions vehicle, it would be a whole different story. If you rip all the EGR stuff off a '78 Chevy small block for example, you will see serious gains. That's when ECUs had roughly five wires going to them and the emissions systems were made to severely limit all outputs. They were the first systems and had lots and lots of issues. Ask anyone who's worked on late 70s and early 80s vehicles of any make/model and they'll tell you the first thing to do when increasing horsepower is to remove all the smog pumps, hardline evap tubes to the intake, charcoal canisters, etc. There was A LOT of junk on those engines.
But we're talking about a 90s vehicle and by then evap systems were pretty streamlined. They rarely just "go bad" (about as often as anything else on a 25 year old vehicle) but serve a purpose. EGR injects exhaust air into the cylinders to reduce combustion temperature. Now, if you've read all about how you don't want these engines to run hot because of headgasket failures, then reducing your combustion temperature sounds like a great idea. Because exhaust gases are forced back into the chamber, it lowers combustion temperature because it is no longer combustible. Simple as that. Mind you, the EGR only functions when the engine is at a high combustion temperature, which is not all the time.
This means the ECU was designed for this. If you remove a component the system is built for, it's going to run different. I'm not going to speculate how it runs because I'm not a "pantseat wisdom" kind of guy, I want actual data. And there is no actual data to support that removing the EGR on these vehicles improves anything at all.
So, removing the EGR:
1. No performance gains i.e. MPG, HP (may actually hamper performance)
2. Higher combustion chamber temperatures
3. May mask underlying engine issues
4. Spews more s*** in the air
Which is why I don't understand the logic of everyone on these forums removing these systems. It's almost one of the first things people do mainly because it's something to do.
I will admit that removing the EGR system and other smog components do clean up the engine bay, but this isn't a 1970 Chevelle. It's a Land Cruiser and the engine bay isn't a thing of beauty by any stretch of the imagination. If it was a show car, then I'm all for it.
