FUEL IN OIL 2010 CUMMINS ISC 8.3

Basically he is wanting you to do a manual Regen with the DEF doser removed from decomp pipe. The outlet NOx sensor reading stabilizes once reached Regen temp, the readings of inlet NOx and outlet NOx should be the same. You will have to open monitor set for aftertreatment overview to view readings.

 

I pull both NOX sensors from the pipe inlet and outlet. If you have the ability to plug the inlet where the sensor goes it is helpful. Downstream not necessary to plug. Lay the sensor probe outside to atmosphere and initiate a regen with Insite. The purpose of the regen is to get the exhaust temps up to get the sensors to come online and start to register. Typically you should see near zero ppm when monitoring with the sensors removed. Plus or minus fluctuations of -30 to + 30 I would consider acceptable. If the outlet hangs positive 100 or more it is likely biased high.

Then there is the bonus of just replacing them with new ones because the buggers are frozen in there to even get them out of the pipes. These sensors won't take much abuse. If you decide to use heat to take out the probe you might as well throw it in the garbage and get a new one.

Other things to check are DEF concentration and that the filter is clean and the tank is free of debris.

 

You probably will choke your brother when you see Nox sensor prices.

 

I know the ones on a Volvo D13 were over $1k. A quick search for the ISC 8.3 online listed one for $976 and change.

 

Shop around, you dont have to buy Cummins parts from Freightliner. Try a larger dealer that might have more purchasing power to get the price down. Older NOX sensor prices are coming down. Should be able to get these around 500 each.

 

I would definitely lean toward the outlet first. This is the the one the ECM is constantly watching to be certain the NOX levels coming out of the tailpipe are at acceptable levels for pass/fail. It also is the one that sets the dosing rate for the DEF. I think the upstream one can be a little more forgiving if that make sense?