This is my 3rd maxima, and I was always under impression that these engines/trannys are like diamonds, forever. It's becoming more apparent that I finally ran into a max that will need a new engine/extensive repair. Sorry for the intro, anyways:

This problem appears when the car is warmed up, at idle I hear a metallic knock, a ticking of sort, as if the valve is hitting the metal cover. It happens at an interval of about two ticks a second, and the volume of the tick can be drowned by an AC compressor (so its not very loud, but audible). The tick/knock is most heard from the right side of the car(passenger side wheel well). When the car is in neutral, and car is being revved at about 2.8-3k+ you can hear the knock (at much faster interval, corresponding to engine speed), and when driving its audible when accelerating, usually only between 1st and 2nd gear.

When I stopped by the shop, thinking it's probably just a pulley bearing, they said it's engine problems, but nothing serious. They said it could do that for many more years and suggested adding Marvel oil and using different viscosity oil.
Yesterday, at close to 100 degrees, I decided to throw as many heads in my car as I can and drive an hour to the beach. Since the AC was on full and music playing I didn't notice anything, just that the car would shake at 55mph+, and some power lose (power lose was probably just due to extreme heat and load). All my tires are balanced, and I just aligned wheels, so on the way back I got to thinking that I should turn down the AC and feel the engine. What I heard sounded horrible! Not something you can drive with for few years. The car kinda sounded as if the engine was overheated-constantly knocking at any rpm, but of course louder when at higher rpm.

The nissan tech guide suggests that my problem appears to be valve seat clearance issue, but now I'm not sure. I don't want to go to a shop blind, because with problems like this, they might know less then someone here on maxima.org.

Looking for any feedback on this, can it be the knock sensor? I've never heard what a faulty knock sensor sounds like. Just trying to gather all the info I can before I spend money.

BTW, There are no engine codes, last code I had went away after few hours. Only thing that might be relevant is when I start the car, after it being off for 2-3 hours or more, I get similar knocking, and the oil light in the dash blinks intermittently, but all that just for a second while the rpm raises, as it drops to normal idle speed of 800 (or whatever, more when car cold) the knocking goes away.

 

the ticking could vavles needing adjustments, the injectors make a ticking sound too. did you ever run low on oil, do you change oil frequently. what grade oil do you use

 

THe only time I ran low was a year ago, and by low I mean 1.5 quarts less then should be, I use 10w30 regular, not synthetic and change oil regularly(never go over 10k, usually 5-6k)

 

what you could do is change your oil, but while its draining, check to see if theres any metal shavings in the oil. it sounds like its rod bearings, i hope it aint though

 

Will try to replace oil with something denser, like 20w40

 

Oil change ot 20w50 did nothing. Guess it is the piston rod bearing

 

My 2002 SE did the same thing and when I took it to the nissan dealer they said it was the crank position sensor and that the engines timing was a tad off or something mine does not do it now (other than when I get bad gas).

 

Did this affect performance at all?

 

Was your engine knocking at idle/at high RPM?