Hi friends,
I had code P219a on my ST that I could not solve. It would come on after fill up, I kept thinking it was that poorly designed capless fuel system (come on, Ford!) I read many forums, watched YouTube etc etc with no clear fix. Here is what I did to fix it, I hope it can help someone else.
*PLEASE NOTE* I work in a shop and have access to professional tools, etc etc if you are not comfortable working on your own car, please consult a professional!
1. Scan code-assess fuel trim
-long term fuel trim was taking away fuel, therefore there was an unmetered fuel source
2. likely culprits were unmetered fuel vapours through EVAP fuel system, but this would (should) come up as a separate code. Could be the purge valve, so I replaced it anyway to rule it out, but of course it did not fix it.
-had to rule out any potential vacuum leaks, I had plumbed my own oil separator in, so I changed everything back to factory to elimate any issues from that. Of course that wasn’t the issue
3. Through process of elimination, the last remaining piece of the puzzle would be the factory PCV/oil separator located under the intake manifold. This job is fairly involved, requires the removal of the intake and starter to get access to this little plastic piece. I cleaned the intake manifold in the solvent take to remove any oil.
-upon removal of intake manifold, it became obvious there was excessive carbon build up on the valves. With the valves closed, I used a carbon remover (you can buy a can at auto supplies stores) and scraped the valves cleaned. You must remove this solution before reassembly!!! Also, do not forget to replace the intake manifold gasket upon reassembly.
4. Final diagnosis: PCV system fail.
I hope this able to help someone else save time and money.
I had code P219a on my ST that I could not solve. It would come on after fill up, I kept thinking it was that poorly designed capless fuel system (come on, Ford!) I read many forums, watched YouTube etc etc with no clear fix. Here is what I did to fix it, I hope it can help someone else.
*PLEASE NOTE* I work in a shop and have access to professional tools, etc etc if you are not comfortable working on your own car, please consult a professional!
1. Scan code-assess fuel trim
-long term fuel trim was taking away fuel, therefore there was an unmetered fuel source
2. likely culprits were unmetered fuel vapours through EVAP fuel system, but this would (should) come up as a separate code. Could be the purge valve, so I replaced it anyway to rule it out, but of course it did not fix it.
-had to rule out any potential vacuum leaks, I had plumbed my own oil separator in, so I changed everything back to factory to elimate any issues from that. Of course that wasn’t the issue
3. Through process of elimination, the last remaining piece of the puzzle would be the factory PCV/oil separator located under the intake manifold. This job is fairly involved, requires the removal of the intake and starter to get access to this little plastic piece. I cleaned the intake manifold in the solvent take to remove any oil.
-upon removal of intake manifold, it became obvious there was excessive carbon build up on the valves. With the valves closed, I used a carbon remover (you can buy a can at auto supplies stores) and scraped the valves cleaned. You must remove this solution before reassembly!!! Also, do not forget to replace the intake manifold gasket upon reassembly.
4. Final diagnosis: PCV system fail.
I hope this able to help someone else save time and money.