Keep getting a po401. I know it's linked to the egr. Today, after changing plugs, for a miss while accelerating, I checked the egr for vacuum leaks with a torch. Found nothing. While the truck was still running, I pulled the small vacuum line from the egr, and nothing changed. Idled, and ran exactly the same. I then noticed barely any vacuum whatsoever from the line. Revving the engine a bit made no difference. Is this low vaccuum proper, or is it supposed to be higher, and may this be what is causing the 401 code to keep popping up?

 

Remove the throttle body and clean it - paying particular attention to the EGR passages, I bet they are plugged.

Suck test the EGR valve with it idling, if the valve itself is working it will stumble and maybe even stall.

There is no vacuum to the valve at idle.

 

Thanks. I cleaned the throttle body a couple months ago. It was pretty disgusting. Maybe I should remove the plenum and clean it as well. The truck runs pretty good though. When the throttle body was dirty on our Mustang, did you ever know it!!! The car ran like crap, and was barely drivable at hwy speeds! When I pulled it to clean it, it was pretty clean when compared to the black sludge I saw on the trucks tb.

 

Yeah, you should take the elbow off and clean it as well. This is where the egr passages are.

 

DWARF, there is no vacuum at the EGR, or hose at idle. Not supposed to be until your at highway speed over about 45 or higher and at light throttle.
Racing engine won't produce any either because the EVR is closed until commanded to open by the computer under the above conditions.
401 code is the results of a 'flow' test done by the computer.
Either there is a blockage or the sensor is faulty that reports the result of the flow test.
Good luck.