1995 Maxima SE PO301

[chanceneale]

Hi folks,

I recently diagnosed my car which suddenly started to vibrate at low speeds (< 40 mph) and when driving in reverse at low speeds. The diagnosis yielded an error that translated to a misfire @ cylinder 1. I unscrewed the coil from the cylinder 1 spark plug (in the back of the engine and on the passenger side). I discovered that the coil head had separated (cracked off) from the coil stem that attaches to the spark plug. I carefully lifted the rubber grommet piece (when the engine had been sitting in 24 F temperature overnight) attached to the stem and the stem was cleanly ligted out of the chamer containing the spark plug. I then removed the spark plug carefully and noticed that it had an oily deposit on it (Platinum NK spark plugs that were replaced 30K miles ago). I installed a brand new spark plug (with silicon dielectric at the tip - ceramic side) and a brand new coil and carefully attached the two screws and power attachment. I cleared the ECU by turning the screw clockwise, 2-sec wait, return it to original position via a counter-clockwise turn and then turning the ignition from on to off. I then proceeded to drive the car on the local road as well as on the highway. The car was much less shaky @ below 40 mph and virtually quiet @ speeds > 40 mph. However, it still was as shaky as before when in reverse mode @ low speed (< 10 mph). After traveling for 15 miles on the highway at 75 mph, the CEL started to blink for about 30 times and then it stayed lit. I reset the light three times and the same things happened at much closer interval. The car is basically back to the same vibrating state as before the surgery. I have not decoded the CEL to determine the error code. I'm assuming it's the same error code but who knows. Have I done this whole procedure correctly? Did I miss something? Does a PO 301 code require other associated parts to be changed too? Should the shaft that I removed the spark plug from be cleaned too? I looked into it with a bright light and it looked clean.

Please help and cc me @ [email protected]

Thanks so much!!

Chance.

[wrenched_1]

wont know until you see if it is the same code.

[574-240sx]

also is that oil coming from a leaky spark plug well gasket?

[chanceneale]

I don't know what this gasket is nor do I know where it is? Something unusual has been happening now in day 7 of the problem. The CEL turns off sometimes. At other times it blinks for about 50 times before turning solid, during driving sessions. I thought the 1995 Maxima SE CEl stayed on after a detected fault until it was reset by turning the screw on the ECU.

Thanks much for any help.

ps. the vibration and hesitation is as bad as ever before.

Chance.