re you saying remove the EGR valve?
If it were me, I'd get rid of the Exhaust Gas Recovery, (EGR) valve. An EGR valve does nothing more than help warm up an engine faster. In cold weather, if you start up your vehicle, and allow it to run a few minutes before moving it, an EGR valve is really not needed.
They started installing these back in the carburetor days of gas engines. The carb needed to do two things in order for an engine to run, and cold weather really made it hard for a carb to do this. A carb needed to atomize and vaporize fuel so it could mix with air and burn more completely, and cold weather caused the fuel to be denser and harder to burn.
Think about taking a cold can from the refrigerator, and the first thing that happens, is moisture condensates on the can and turns it into a liquid, from being a vapor in the air. The same thing happens with gasoline in a cold engine, and the engine cannot burn gasoline in a liquid form. It needs to be a vapor form, and getting the engine hot quickly turns liquid gas, into a burnable vapor. This also causes your MPG to drop because you needed more fuel to be pumped into the engine, just to get a small amount of it to turn into a vapor. This is also why we "CHOKED" the cold engine, to restrict air flow and make the air fuel mixture richer.
Most fuel went unburned in a cold engine, and now if you were driving a cold engine, even more fuel had to be run through the engine to move the vehicle, and that meant more fuel went unburned, and more pollution, and lower MPG.
The fix was we need to warm up the area around the carb as fast as possible so the air would warm up, and the fuel would then start to vaporize, and the engine would run more efficiently.
How they did this was with an EGR valve.
It does not matter how cold an engine is, exhaust gases are VERY hot, and the idea was to reroute those hot gases in a cross over in the intake manifold so it would get hot faster, and once the engine was warm enough, the EGR valve would close and the exhaust would be routed back to its normal path out the tail pipe.
The problem with the EGR valve, is the intake was cold, and remember what happens with fuel when it's cold, it turns into a liquid form again, and the exhaust, while hot at first, cooled quickly as it gave up its heat to the intake manifold and that liquid would start to gunk and carbon up the cross over, and eventually plug the cross over or worse, the EGR would stick in the open position and cause the manifold to get too hot, and thus vapor lock a carb or turn the fuel into a vapor inside the carb, and not in the intake manifold and your engine won't run in that condition.
I'm sure many have heard the term vapor locked, well that's what happens.
While I'm not sure how the Roxor is setup exactly, the principle of operation is the same. The EGR in a diesel is the same thing, it reroutes hot exhaust gases to warm up the intake manifold or cylinder head faster and that warms up the air going into the combustion chamber.
Is the EGR valve really needed.....in my worthless opinion, no, but what the hell do I know. Just let your engine run at idle for a few minutes before moving it, and you'll be fine. The EGR did nothing but try to increase fleet milage and reduce pollution to meet gooberment mandates put on auto manufacturers and did nothing to increase engine life or drivability. In fact, it caused more problems in the long run, and I have seen more plugged intakes than I care to remember.
Back in the 80's I heard Ford rep say once that 95% of all the crap hung on engines these days is only used until the engine is warmed up and then they're just along for the ride. I have no clue how true that 95% figure was, but I know most are just for cold startups.
Me, I start the vehicle, give it a minute to warm up in the summer, and five minutes in the winter, and that alone will do more than all these add on things like EGR valves.
