Mine seems to be getting worse now. If you haven't read the other threads, let me emphasize this is NOT low octane ping. The problem starts just under 2000 rpm at around 40mph with no or little throttle.

Mine was very light and only happened right around 40mph. Now it does it all the way up the street from 20mph to 40mph but still under 2000 rpm. Does it when it's cold and does it when its warmed up.

I've tried cleaners, no help. I won't be changing the plugs for another 15k but does anyone think a colder/hotter plug may help?

 

If you've got enough money to throw at it you could try backing the plugs down a step colder (from the stock NGK -5 to a -6) which seems to alleviate the problem in FI setups and might help you. As a last-case desperate measure take it to a nearby location with a Consult II and get the timing advance backed down 2 deg. or so from stock and see if that helps any.

But pinging is more common under load...not no-load conditions. Does the car feel like it's got a miss/misfire when the pinging noise is occurring? Any CEL? You might also want to buy/borrow/steal an OBDII scan tool and see if the knock sensor is pulling timing advance when the noise occurs, this should help you diagnose either a bad knock sensor or a "phantom" ping (not detonation but some other drivetrain noise.)

 

Thanks for the reply paralyse.

There are others on the board with this problem, perhaps they will chime in. I don't know if it is pinging, but it sounds just like it only lighter. I've dealt with ping on several Fords where a gas tank cleaner or new plugs/wires cures it. The pinging in those cars was always under load on cheap gas, this is completely different.

Under load the car exhibits no hesitation and no pinging. While coasting down or lightly accelerating, there is a pinging sound that stops when the car gets over 2200 rpm or 40 miles per hour. No CEL and definately not drivetrain noise.

Those of us that have it, think there may be a design problem with the intake manifold causing this (maybe with the vacuum activated stage). One thing I noticed on mine (not sure if it is common with the others) were pools of oil in the intake manifold.

 

Looks like Altima's have it too:

http://www.nissanclub.com/forums/sho...ht=spark+plugs

http://www.nissanclub.com/forums/sho...ht=spark+plugs

 

Oil coming from PCV system maybe? You could try installing a Spec V-style oil catch can in-line with the PCV and see if it loads up with oil. Oil pooling up in the intake manifold can't be good, as it would greatly affect the flow characteristics of the manifold. I don't think it is getting into the chamber or you would have fouled plugs.

If you have access to a flow bench you could flow test a stock VQ35 manifold and see what the flow rate is, if it drops off or acts weird with the flow around the vacuum that would be generated at 2200 rpm then you would know. All my (very limited) experience is with small-block Chevy tuning but the same principles should apply to any IC engine.

It would also be interesting if you had a way to see the AFR when the noise was occurring, then you could determine if it was leaning out or going too rich. Maybe a bug in the MAF or in the ECU fuel/spark map is screwing it up.

If you can get the problem to occur in a no-load environment take a mechanic's stethoscope and listen to determine where the noise is coming from -- heads, block, intake area...that will at least tell you where to start, and verify if it's a true detonation or if it's a "phantom" ping like I mentioned above.

 

Thanks again paralyse, take a look at those site if you get a chance. One theory I've read was that Nissan was a little too over zealous with the fuel mapping and the computer is extra conservative during that portion.

Like you said though, oil in there can't be good. I changed the PCV out at 30k, may go in and vacuum the oil out to see if that changes anything. I don't recall hearing it before 10k miles.

 

May sound stupid, but its not another case of the heat shield rattle is it?

 

Hey guys - I am having the same problem. Now I used to own a Jeep Wrangler and had the same sound due to sticky lifters. Wonder if it could be the same thing. The car is performing well, but the ticking/knocking sound is rapid-fire, just audible over the engine, and is at no-gas 2k-4kRPM around 30-40 MPH. Was there resolution on this?

 

http://forums.maxima.org/showthread.php?t=359472
Heres a thread which i responded to about the same problem. But it may be no problem at all, performance is not reduced like in most pinging situations that occur under moderate to heavy throttle. The suggestion of the PCV valve is interesting, since i've not replaced mine at 34K now and never noticed until about 30 K or so miles. Was getting 19-20 MPG this summer when I first noticed it, now i'm down to about 17-18. Not too worried about it at this point but will get PCV valve replaced soon.

 

Very interesting indeed - as I just had my PVC replaced at 36K and my SES went off. THey had to re-program the ECU and since I've had 2-3 mpg drop. Time to call my friends at the dealership.

 

I replaced my PVC at 30k...no change.

 

Haven't changed my PVC valve yet. I would assume if it functions (by testing it) it doesn't need replacing. This may be a dumn question but does anyone think that a grounding kit would have any impact on my knock issues? Also how does one test the voltage of their knock sensor to see if it is working properly?
Thanks

 

Any updates?

 

I had a similar problem. 2000 Maxima. I know engine knock/pinging when I hear it, and though some keep suggesting heat shield (due to it perhaps vibrating a certain way at specific RPM), I knew that was NOT what I was experiencing. I could give it a lot more gas (or less) and get it to quit, but in that 1200-2000 RPM range, this started really bothering me. I always use Chevron 93 octane so it was not the gas.

I replaced my plugs, no change. Finally I broke down and went to the dealer (after the service engine light also came on). They said it was the MAF. They replaced it, and said they also cleaned out the intake manifold/fuel injectors, and ALL FIXED!!! First they said it would be $850. When I complained and mentioned how many people on the web were complaining about these MAF failures (and ignition coil issues), they dropped it to $580. Still a lot but it feels great to finally have NO PING and great running engine.

 

Looks like you've covered most of it, but in a few years on the org, the three things I've heard that cause this are:

• As you'll see in the manual, the 3.5 is designed to ping under light load. This is normal.
• The PCV valve mod (oil catcher) fixed the pinging for several people.
• Dirty throttle body caused others.

Good luck!

 

Don't get me wrong, but i can't believe it was the MAF, cuz my previous Max(i30) had the same pinging as my current Maxima... and after changing that MAF, the problem was still there... Probably, cleaning the manifolds and injectors helped in your case!?

How long have you been driving without that issue and did the dealer clean the TB as well...?
Thx

 

Not sure what TB stands for, but in addition to the MAF replacement, they did a "fuel injector flush service", and said they reset the computer.

I only have 61K miles on my 2000. I started noticing the light pinging over a yr ago. It kept getting a little worse, and by this summer had gotten really loud/annoying and I was worried about it hurting my engine. Since the MAF replacement about a month ago, the engine is running perfect! No ping at all under any conditions.

If it was not the MAF, some other combo of factors may have solved it (computer reprogram, fuel injector flush?), I am just grateful for it to finally be cured.

 

TB = Throttle body

 

The theory is that it is oil dripping in from puddles in the UIM. I've seen the puddles, as I was cleaning out the AAI part of the UIM. Using a catch-can, can reduce the amount of oil that gets collected. Inducing oil into the intake will lower the octane (hence the ping). Flow is greatest at idle from the PCV.

I believe the cleaning probably removed the "puddles" from your UIM, but give it time...it will return. I'd suggest adding a catch-can to your PCV.

 

I came to the conclusion that the 2K rpm rattle is indeed the timing chain clattering. It happens even if my oil level is high. I'm guessing the tensioner or something could be replaced, but that's a b!tch and half. I doubt it has anything to do w/ reliability so i'm just going to live with it.

 

man i got this exact same problem driving me nuts!!! i dunno if its a rattling noise or pinging noise.. cause i dont know what pinging sounds like.. anyhow at around 2k rpm it starts to make that noise or when there is load.. I went to the dealership and they said it was not my heat shield, and blamed it on my cold air intake which i think is a bunch of crap. When I did a oil change at my buddies shop they added oil thickener thinking that my timing chain is not lubing properly.. still i hear the rattle.. i have now bought deno irridium spark plugs and am going to get them installed this weekend.. if this doesnt not fix it i dont know what to do.. i hear people talking about a ecu upgrade for hesitation.. do you think that would hlep fix it.. i dont even know what hesitation means in car terms?? anyone have any other suggestions or do i have to take it back to dealer.. but i think they will most likely blame it on my cold air intake