If the timing is off it will have a low and rough idle, AND it should be throwing a random misfire code. My guess is to ask if the cat has ever been changed, to her knowledge, and look into it possibly clogging with debris and then maybe unblocking and running good again. IIRC the dx has the manifold cat right? Pull the manifold off and check the cat. Also, check the ignition timing, or just advance the timing and take it for a quick drive to see how she runs then.


Michael