Join Date: Oct 2016
Thanked 6 Times in 4 Posts
iTrader Score: 0 reviews
6.7 Cummins EGR disable/ reduce, eliminate active regen
Just subscribed to Cummins Forum. I dont have permissions to start a new thread and am going to offer new information on this topic.There are a lot of people that don’t want to remove the crap named emissions equipment and risk fines etc. I did a lot of reading on the subject and did come up with some solutions to help with the 2007.5-2012 Rams. I cannot report on the def trucks but this may work on them as well. Will most likely work with any DPF truck including Duramax and Powerstrokes.
Reduce or eliminate active regen process: There are 2 types of Regen processes associated with DPF equipped trucks. Active Regen that all are very familiar with, when the trucks ECM commands more post injection fuel added to the exhaust stoke triggering a burn off of soot build up in the DPF filter. This normally happens every 50-100 miles in stock trucks and your mileage takes a dump. The second type of Regen, Passive regen usually goes unnoticed and occurs when towing or longer highway runs. The exhaust gases remain hot enough for a sustained amount of time that allows the soot in the DPF to burn off. Passive regen does not hurt your mpg.
After thinking this over, I decided to come up with a mod to promote passive regen, thus reducing/eliminating the negatives of active regen. To keep the exhaust gasses hot enough requires insulation to reduce heat loss. I purchased 50ft of exhaust header wrap with an aluminum coating on one side. 50ft was enough to wrap from the downstream side of the Cat to the DPF and wrap the DPF. The metal straps are not necessary, I preferred using bully wire about every 1 1/2'. Wrapping sections makes it easier to wrap and remove sections of pipe if desired. I didn’t remove any sections by the way and spent about 30-45 minutes wrapping. It was tricky wrapping the DPF filter due to the shape, take your time, you may want to wrap in an X shape to get the funnel shape parts of the DPF.
No need to worry about this mod affecting EGTs, since it has nothing to do with temperatures coming from the exhaust port.
So, how does it work? I have had my pipe wrapped for 2 weeks and approx 500 miles and see a big improvement. I have not had the instant mpg pegged to the left indicating active regen once!! Even city driving it has not gone into a full regen. It appeared to do an abbreviated one, my instant did some flickering to the left like the ECM may have added a minute amount of post injection. My mpg is up about 1 1/2 to 2 mpg from what I can see so far.
EGR mod: Another mod I have been working on is to reduce/eliminate EGR function. I was hesitant on this subject since many subscribers stated limp mode and dealer trips were the result. I knew the pre 2013 Rams have over active EGR and Ram greatly reduced the amount of EGR in the 2013 & up trucks. Seems like a better approach is to fool the EGR temperature sensor. The sensor reads resistance as exhaust temp. Seems like people have unplugged the EGR temp sensor and put a resistor in the circuit to send a low temperature signal to the ECM. When the ECM sees this, the EGR valve is kept closed. While this sounds like the Holy Grail, there are some minor short falls. I used a 1/4 watt, 10 ohm resistor. Bend the ends to form a U shape. Then bend a small amount of the 2 end wires back on itself making it double thick. Insert one end of the resistor into each socket of the EGR temp connector. This simulates the sensor and the ECM thinks its plugged in. From what I can tell the EGR is staying closed. I noticed a slightly louder engine idle to. Mabe someone can answer why that is? I think its due to fresh air vs crap air or did the map change to a colder climate one? It works pretty darn well with 1 issue, you will eventually trigger a CEL, P040 open EGR circuit. I have gone 1 to 2 days between codes and have not caused a limp condition or power loss. I simply clear the code since I don’t like driving with a CEL but I don’t see any negative performance issues with this method. Duramax owners have a Holy Grail called the finger stick. Anyone try making one for Cummins??