Cummins ISX- (2003)

once it gets completely clogged it will derate the engine and the black smoke will become steady look like a #### freight train. took me 3000 dollars to figure out it was the #### sensor. Cummings told me it was a design defect on there first family of egr engines. soot builds up and blocks the diaphragm from working then starts building up in the metal lines...

 

sorry it is on the drivers side 3/4 of the way back. small hands help my wife became a champ of pulling it and reinstalling it.....I love a woman who can wrench

 

did you blow the lines out connected to the sensor....when my problem started they were so clogged i had to replace them

 

Before you spend alot of $$ 1st just pull the valve cover and CK. the cam an rocker arms for wear,look at lobes on injector camshaft for wear you can do a quick ck. with a feeler gauge to see how far off some of the settings are on valves that stopped closed,if the cams lobes are not worn off and if the intake and EX. valves are still being opened all the way you can fix the egr?

 

You may have hit a bump or something and the egr valve closed around the same time.
If you take the egr valve apart,it's probably full of soot. If your getting rid of the truck,you can remove and clean it. If you take the back housing off,you'll see the gears are clogged with soot.

 

Unplug the square connector in the centre of the engine on the drivers side. It is the wiring harness plug for
the jake brake. My wiring harness is oil soaked and as such is shorting and causing the jake to come on by itself. Once unpluged the issue went away. Give it a go and see what happens.

 

Thanks for coming back with the fix. Too many members are only on here to get the free answers they need and then disappear.

 

The pressure differential sensor has hydraulic brake like metal lines that get plugged up with soot. Worth checking to make sure they were cleaned.