I just bought a 2000 f150 4x4 4.6l with 252k miles. The check engine light has been on since I bought it. I had it checked at autozone and had the p0401 that seems to happen a lot on these trucks. My question is before I tear into taking the throttle body off and cleaning the egr ports. I just want to see if I have the symptoms of plugged egr ports. I'm having no drivability issues. The idle is as smooth as can be no jumping at all and when driving no missing or struggling at highway speeds. I have all of the receipts from where the previous owner (one owner truck) had the truck worked on at the dealership it's whole life. And I know at one time he had the egr valve replaced and the ports cleaned. Not sure the mileage it was at when that work was done so I'll have to look at that for sure.

Thanks for any advice

 

i think your on the right track..

F150 EGR problem P0401,.... solved - Ford F150 Forum

 

You can check egr ports in the throttle body, by sucking on the egr valve line port engine idling, if the engine slows to almost a stall the ports are clear. just my .02

 

Thanks. I used my little hand vacuum pump and applied vacuum to the egr valve and the idle didn't change at all. I wasn't sure if that would mean the ports were plugged or if the valve was stuck and broke. Cleaning is the cheapest route so I'll start with that and go from there. It's about 15 degrees outside today so it's probably not gonna happen today. Is there anything I need to watch out for while I'm taking stuff apart? Ie easily broken bolts, wrench sizes stuff like before I dig into it I like to have all my ducks in a row.

Thanks again

 

Now just make sure the egr tube is good at the exhaust manifold, this rots out. As far as removing the throttle body it pretty cut and dry just a pain sometimes as the egr valve nuts can be corroted or the egr nut on the tube is on there pretty tight, also try not to spray the TPS with cleaner, gaskets are reusable, I use the high temp antiseize on egr tube nuts. always check the dpfe lines for cracking.

 

Cool thanks. I'll hopefully try that soon.

 

Well I braved the cold and went out and took the throttle off and cleaned it. The ports were completely clogged with carbon. Took it for a test drive and went good. Seemed to be smoking a little bit. I'm thinking some carb cleaner is still burning off I sprayed a bunch on everything in the intake. I went into the gas station and came back out fired it up and after a couple seconds the check engine light came back on. So back to square one.