Still trying to get the truck to stop coding insufficient egr florw. have replaced sensor, valve and solenoid. the tubes were blown out with compressed air when the valve was replaced. Is there a better way to clean them out?

 

Tubes? Do you mean the tubes that come off the exhaust manifold to the DPFE? If so, those aren't the ones to clean. The ones you want to scrub out are in the throttle body elbow that bolts to the upper intake manifold. I use a small pick to get the bigger stuff out, then a .22 caliber bore brush with carb cleaner to scrub out as much as I can. It just takes plain ol' elbow grease and some chemicals to get those ports cleaned.

 

You probably need to clean out the vents going from the EGR valve into the in-take. You generally need to remove the intake elbo to clean the carbon build up out of the vents/tubes. Once removed, you can usually just break up the carbon build-up with a screw driver.

The rubber tubes going to the DPFE sensor seldem get clogged. The most common error when putting the new sensor on is to put the hoses on the wrong input. One input is slightly larger than the other. Just because the "Big" input was on the left on the old sensor, does not mean it's on the left on the new sensor. If the hoses get swapped, you'll still get code P0401.

 

I can't seem to identify these tubes. acn somebody give me a more detailed description of where they are?

 

These tubes are part of the upper intake plenum. They go from the EGR valve into and thru the upper intake plenum. They are know to clog up mostly on 4.6L engine with quite a few miles on the engine.