1996 Nissan Maxima Code P1320: Ignition System Fault, #1 Cylinder Misfire, Vibration and Loss of Power
Two weeks ago, my check engine light came on and began flashing as I approached my driveway. Using the CARMD tool, I retrieved Diagnostic Trouble Code P1320, which points to an ignition system issue—specifically related to spark, coils, or misfires. My mechanic initially found that cylinder #1 is not firing. He ruled out faulty ignition coils as the root cause and suggested an internal problem. The vehicle exhibits a noticeable vibration when in gear, accompanied by a misfire sound, and sometimes nearly stalls—though I did not drive it aggressively; it was towed to the shop. Seeking a second opinion, I visited a Nissan dealership. They diagnosed faulty ignition coils and spark plugs, recommending replacement with OEM parts. The components were replaced yesterday, but the issue persists. While the vibration has significantly decreased, the car still lacks power during acceleration and continues to misfire—though less severely than before. The check engine light remains on but no longer flashes. I will re-run CARMD later today to check for any new or updated codes. I'm looking for possible overlooked causes that could be contributing to this ongoing issue. Additional note: The starter was replaced about six months ago, and there are no signs of electrical faults at the battery or alternator.
Since you've identified cylinder #1 as not firing: - Check for 12V at the coil connector—this is typically a red wire. Verify voltage specifically at the #1 coil terminal. - The yellow-red (Y/R) wire carries the signal; it should NOT be grounded and should pulse to ground during engine cranking. - A preliminary guess: the ignition coil may still be faulty. Try replacing it with an OEM Nissan coil, as these are known to perform better in older Maxima models.