This past week my Max has begun making a clicking sound at idle. The sound increases with rpm's although I cant hear it past 2500 rpm. But as soon as a release the throttle and the engine returns to idle I can hear the clicking sound slowing to a steady state at idle. I've opened the hood and listened around during idle and the sound is coming from the valvetrain. Not sure if its the valves themselves or possibly the cams/timing chain. Anyone have any clue what this is and how to remedy this problem? I need help as soon as possible.

 

I think my car is making the same noise. Turn your AC off...if the noise goes away...you know what it is.

 

It is important to identify the source of the noise. A four-foot length
of small diameter rubber vacuum hose will help you do this. You can buy
the hose in any auto parts store. They typically sell it in bulk for about
US$0.50 per foot. Start the engine and let it idle. Put one end of the
hose in your ear and the other end near any suspected source of noise.
The engine compartment presents a cacophony of sound. The benefit
of the hose is that it isolates the sound from one specific area. Work safely!
Avoid contact with any moving parts!

You may find it interesting to explore the sounds of your engine with this
inexpensive tool. Each moving part has its own characteristic sound. For
example, listen to the muted clicking of the fuel injectors. They should
all sound alike. If you find one with a different sound (or no sound at
all) you have found a problem.

The dealer's service department is equipped with high-tech diagnostic
instruments. These are wonderful devices but they are expensive and the
dealer has to recover his cost by charging you for diagnostic time.
Sometimes the home mechanic can do legitimate diagnostic work with
nothing more than a rubber tube.

 

I'll try the hose this evening, but if it sound was coming from the valves what could the problem be and how could it be solved?

By the way "Max I Am" my AC was off, I actually hate using AC.

 

It may that one or more of your valves needs to be ajusted...or set to factory setting..

 

Let's not dwell on hypothetical questions. When you have more facts post them here.

 

OFF TOPIC: Hey I'm a guy. What's with the "Just the facts, ma'm. Did I miss something here???

 

Was this a quote from Die Hard 2?

 

"Just the facts, ma'm.", is a famous line from a 50's TV cop show, Dragnet.

I recall that VQ engines don't have valve adjusters. Ticking from the engine could be timing chain, possibly an injector, or something loose. How often do timing chain guides & tensioners go bad on these engines?

 

Years ago Jack Webb starred as Sgt. Joe Friday of the Los Angeles Police Department in the popular television show Dragnet. Friday was a hardboiled cop who pursued the bad guy relentlessly. In almost every episode of he would be interviewing a witness who rambled on and engaged in speculation. Friday cut them short with what became his signature phrase: "Just the facts ma'm, just the facts."

 

Nissan does not include valve clearance adjustment with any scheduled maintenance. It should be done if and when the valves become noisy. On most cars this service will never be needed.

Adjusting valve clearance not as simple as turning an adjustment screw. Each cam lobe bears directly against a disk-shaped steel shim of precisely machined dimensions. Changing valve clearance is done by removing the shim and substituting another with a different thickness. This service procedure requires special tools. The shims are made in thicknesses ranging from 2.32mm to 2.95mm. They can be purchased from the dealer. I'm not aware of any other source for these shims.

 

I have a similar issue with my Max, although the clicking doesn't continue (although I don't think it does) I am also wondering what to check, if it's not the valves?

 

You could read an earlier post in this thread which tells you how to use a vacuum hose as a diagnostic listening aid...

 

How loud is the clicking sound? Because I hear a similiar sound but it is very quiet, and cannot be heard unless the hood is up and you put your ear close to the engine.

 

That's your engine running Get used to it, no combustion engine runs silently.

Seriously though, if you can't hear it unless you stick your head right by the engine then there is definitely nothing wrong. Just normal sounds of the engine working.

 

This might be completely wrong, but I was told the when my engine was making a clicking noise like the one you described that my fuel injectors were kinda clogged. I had them cleaned/treated and the sound went away. I don't know when the last time you had yours cleaned, but it might be something to think about.

 

Ya thats what I thought, its been there the 6 months Ive had the car and I never even thought about it until I read this post, but the original poster never said how loud of a sound he was hearing, so I just asked to be sure

 

I purchased a 4 ft length of vacuum hose (Autozone $.89/ft) and listened around my engine compartment for a few minutes.

Here are my findings: The sound is not coming from the valves, nor the timing chain. I believe the sound is from the injectors. I cant find a pic that is small enough but this is the best I can explain it (6 branches coming from the fuel rail to each cylinder, right?)

If it helps I'm going to perform a full tune up this weekend (recently crossed 100k). If its the injectors how do I remedy this problem?

Keep the suggestions coming! Need to keep my Max running as healthy as possible.

 

Hang onto that hose. You will find it useful.

If the injectors are clicking, you don't have a problem. It is normal for them to click. Here's a quote from Haynes, page 4-9:
With the engine running, place an automotive stethoscope against each injector, one at a time, and listen for a clicking sound, indicating operation (see illustration). If you don't have a stethoscope, you can place the tip of a long screwdriver against the injector and listen through the handle.
Compare the click you hear from each injector. If one sounds distinctly different from the other five, then that one injector is sick.

I can imagine that a dealer would have charged you for one hour of labor to tell you "that sound is normal."

 

I think my friend told me this because mine were abnormally loud, like you could hear it across the parking lot, and I was also getting some white smoke from the tail pipe when the car started after sitting all night. . . So I think mine were at a point where they needed to be cleaned. . . I took mine to a local oil change place and had them cleaned, but I am sure fuel injector cleaner would work just as well.