My truck is a 99 F150 5.4. A couple days ago it threw both of these codes. I did some searching and found that dirty EGR ports could be the culprit. So I did the test where you pull the green vacuum hose from the EGR, and the truck started idling really rough. So this means my ports should be clear correct?

Now before i go replacing the DPFE sensor, I want to make sure that another issue the truck has isn't causing this. I have a broken stud on my passenger side manifold that I will be getting fixed in a couple months. I can hear the exhaust leak when I rev. Could this have caused this code? Perhaps it has progressively gotten worse?

I have also noticed that while the truck idles fine, under light to medium throttle there is a slight shudder. It was not doing this 2 weeks ago before the CEL came on.

Please let me know your thoughts and thanks!

 

a vacuum leak will throw that code you might want to check the pcv hose the rubber elbows can crack and corrode

 

Both of what codes? I just see one. Post the other code as well.

Yes,- a exhaust leak/ EGR pipe leak @ the manifold can and has thrown 401's. Service Exhaust (manifold) leak/ reboot your PCM. Check both manifolds and the EGR/ manifold port fitting.

No concern on the 401, - correct the manifolds and /or leaks in the "Y" / reboot.

If you haven't serviced your throttle body in awhile, it's a good idea to do so when you get a chance . The 5fours won't usually plug the ports, the 4six does all the time. The EGR system routing between the two engines are quite a bit different. The valve itself is different as well, - regardless, the 5fours will seal off about 1/3 rd of it's EGR ports. Yes it may pass the "suck test" , but if restricted, -your pushing that much closer to your factory set program parameter margins. Problems could be accumulating.

That could mean, for instance - A manifold leak on the opposite side of the engine + a partial blocked EGR port,- could be enough to drop you outside of said parameters, thus produce a DTC.

Good Luck.

 

Thanks for the info.

FYI, the other code was P1000 which as I understand is just that the PCM has not completed a full round of checks.

 

Right, your monitors haven't completed yet. The EVAP monitor can take awhile, -conditions must be met. - Unless you force it to run.

 

Just to follow up on this, I got the exhaust leak fixed, and still had the code. Replaced the DPFE sensor, and so far so good.