Like many 80 owners, I was having a low-rpm ping which started last summer and continued into the cooler weather. Did all the maintenance, tune-up, etc. For grins, I picked up some Redline Fuel System cleaner from Summit Racing and used one bottle each for three consecutive fillups. Voila! ping was gone.
Feeling smug about that one, a week later I got the P401, EGR problem. Did a ton of reading here on 'Mud and decided to try the cheap route first. I disassembled the EGR system and removed all vacuum lines. I ran Seafoam through the vacuum lines; and I cleaned up the EGR filter and pot with Seafoam. Then I reconnected all vac lines and dribbled some Seafoam into them. Lastly, I pulled the PCV vent hose from the valve cover - other end connects to the throttle body, in front of the throttle plate - and poured Seafoam into it while the truck was running. I turned it off after about 15 seconds, let it sit for a while, started it back up, and sucked more Seafoam in through a vacuum line, turned it off and let it sit.
At next startup, after it got done smoking, the dang thing ran smoother than it has since I got it and my P401 is gone! I am very surprised at how smooth it is, and am anxious to see if my mpg has been affected.
When reinstalling the vacuum lines to the EGR, I pulled the two from the throttle body then was having a hell of a time reinstalling them through the throttle/cruise mechanism. Said enough, hacked them down to about 8 inches, sheathed them, and just ran them direct over the throttle. Why Mr. T ran them down the TB is a mystery.............
Feeling smug about that one, a week later I got the P401, EGR problem. Did a ton of reading here on 'Mud and decided to try the cheap route first. I disassembled the EGR system and removed all vacuum lines. I ran Seafoam through the vacuum lines; and I cleaned up the EGR filter and pot with Seafoam. Then I reconnected all vac lines and dribbled some Seafoam into them. Lastly, I pulled the PCV vent hose from the valve cover - other end connects to the throttle body, in front of the throttle plate - and poured Seafoam into it while the truck was running. I turned it off after about 15 seconds, let it sit for a while, started it back up, and sucked more Seafoam in through a vacuum line, turned it off and let it sit.
At next startup, after it got done smoking, the dang thing ran smoother than it has since I got it and my P401 is gone! I am very surprised at how smooth it is, and am anxious to see if my mpg has been affected.
When reinstalling the vacuum lines to the EGR, I pulled the two from the throttle body then was having a hell of a time reinstalling them through the throttle/cruise mechanism. Said enough, hacked them down to about 8 inches, sheathed them, and just ran them direct over the throttle. Why Mr. T ran them down the TB is a mystery.............
It usually goes away during cold dry weather (which leads me to think that a vacuum hose might need to be cleaned).