Q: Code p1391

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The car originally stalled on us while we were driving. So I took it to my garage and started working on it saw that there was a code for p 1391 so I changed both sensors that did not fix the problem. The car started missing and said that there was a timing issue so we change the timing belt and put a whole new kit on. That did not fix the problem so we moved on to the computer replaced computer had dealership flash it. That did not fix the problem did a tune-up even put on a new coil pack that did not fix the problem. Car is a little hard to start but will run fine up until the point where it warms up.

My car has 12583 miles.
My car has an automatic transmission.

Hi there:

Although the O2 sensors can cause intermittent starting problems, one of the most overlooked components that can trigger this OBD-II error codes and cause the issues you’re describing is a camshaft position sensor, or the electrical harness attached to the O2 sensors. If these items were not replaced during the dealership service; it’s possible that this is the source of your problem. However, it’s always best to have a professional mobile mechanic complete a car is hard to start inspection; so they can pinpoint the source of this problem first before parts are ordered or replaced.

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