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P219A and P219B

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Howdy all,

I just recently purchased a small bluetooth OBDII reader ( to use with the Torque App on my Tablet. I noticed while checking the dianostic stuff there were two errors only while using the Trackey. I did have my car show a check engine light 3 times total. 2 times with the silver key (limp mode) and 1 time with the Trackey. Those happened months ago. Does anyone have any information on these errors? I have read on other forums that has to do with the O2 sensors. Could be an exhaust leak or bad sensor. Has anyone else had this happen to them yet? I have searched the forum and have turned up nothing.


#LS-378 - So many Porsche's, so little time....
According to Ford documentation it's the A/F ratio imbalance monitor kicking in. See It does seem related to the O2 sensor readings and based on what I saw on other forums it may due to 1) faulty cats, 2) removal of cats, or 3) a leak in the exhaust pipes.

I'd take it back to the dealer and let them run a diag on it. My suspicion is that it was a one-off occurrence and they will just clear the codes and be done with it. That said, there may be other codes in the PCM that they will have access to that you do not, since a quick scan with an OBD-II reader only shows the last round of DTC codes. Others can be stored in non-volatile memory.

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