blocking the tube from EGR to intake ........thoughts anyone ??????

475 ISX, unplugged mine in the cold (closed) position and gained a full point on mpg. Throws an amber check engine light and code though. Otherwise it made a big difference in fuel economy. I had my turbo rebuilt recently and the shop plugged the egr back in and I ran with it like that for the last 2000 miles, and am not getting as good mpg now, so I will probably unplug it again.

 

D12 got EGR pos sensors only, no delta sensor and when you block egr ECM work like D12D Euro-3. Really Volvo D12D engine got no VGT like ISX so no boost strategy related with EGR.

But new D13 engines cant work properly w/o EGR

 

Please explain "boost strategy" for ISX. Thanks in advance.

 

I'll try to explane. VGT is not so accurate thing and may supply engine with too much air (too high boost pressure for fuel) and fuel:air mixture goes lean making more NOx and more combustion temperature. EGR is really accurate thing to correct VGT mistakes.

D12D was designed as non EGR engine. No EGR, no VGT, no problem, but too meet newer emissions they put two egr in this engine to reduce NOx only, not to correct VGT inaccurance, like cummins did.

 

I sugest no MPG difference... if you block EPG that works well

 

no MPG difference... but the truck runs cooler, cleaner, and I'm not replacing the EGR's every year

 

so how did you block your egrs??
Thank you!