Yes the injectors tick. But, the ticking I'm complaining about is in the rocker cover. No doubt about it!

 

Loud ticking that varies with RPM is a VQ trait. That's a fact. Now maybe he does have lifter issue, but it would be a very rare case for a VQ.

BTW, it's a Nissan thing. Titans suffer from injector tick. http://www.titantalk.com/forums/tita...ctor-tick.html VQ40 Frontiers http://www.clubfrontier.org/forums/f...e-noise-40876/ VQ40 xterras http://x.nissanhelp.com/forums/xterr...pet-noise.html

 

Okay, so is it coming from just one cover or both? Have you pin-pointed the exact location of the tick? I strongly suggest you take the car to a reputable mechanic that knows VQs and get their opinion before diving into this project. It's very complicated because a cam(s) will need to come out, the timing cover removed, up to three timing chains removed, new gaskets on the covers and spark plugs, liquid gaskets, then you get to measure the shims (being referred to as "lifters" in this thread) and pray you get the measurement correct. Last I heard, this was about 10 hour job for a Nissan tech.

 

BTW, excessive valve lash will typically have a metallic tap, not a tick.

 

Its in the drivers side rocker and sounds metallic. I realize its a drawn out procedure, I have the service manual, but I just cant see dropping $1000-1500 to have the dealer do this. This would be my first rodeo with a VQ, but not my first with DOHC.

Have you (Dave) ever done this job or cams? How deep into the VQ's have you been? Maybe I can call on you for tips while Im in this endeavor.

BTW...I see these ads for an angled plenm spacer. I am looking into making one of these for myself. I have several EDM's and a pretty nice waterjet at work. While I have the plenum off to look into the valve noise, I'll probably have the pattern digitized and I'll let you know as this progresses

 

The valve lash adjustment on this engine is probably the one job I would take to the dealership. It is an extensive procedure that requires patience and training. I have done a similar procedure with my DOHC Taurus SHO. Should you decide to tackle this yourself feel free to PM me with any help.

Run the BG-MOA and the BG44. These are designed to clean the crank case and your injectors of gunk and build up. If you lived close I would send you to a Nissan technician out my way that could do this job for you on the side for a fraction of the cost.

 

Make sure to verify that the tick you're hearing isn't coming from a particular part of the fuel system. The name of part escapes me right now, but it sits more towards the front of the engine, but near the rocker cover (I believe drivers side). There's a bushing (or maybe lack of one) that can cause a knocking as the fuel system cycles. It's a problem that afflicts quite a few 03/04 sedans.

I have not done a cam swap on any of my VQs. Though, I have helped a friend swap VQ35 heads on to his VQ30 in his 98 Maxima and then later a VQ35 into the same car. The procedure is pretty complicated and far easier when the motor is out of the car. I don't think there's much I could help you with if you've got the FSM. The procedure is layed out pretty clearly.


Even OCG35 will probably agree with me on this, just spend the money on the Motordyne spacer. It's $240 well spent. You could make one yourself, but for $240, you're going to get a part with aircraft grade machining, all the bolts, and plastic spacers to make sure it works correctly. You would spend countless hours trying to get the measurements exactly right and the spacer exactly true. You'd waste a lot of material. You'd also have try to find the internal plastic spacer stands and all the various length bolts to attach the plenum. The angled spacers have a history of subpar construction and questionable gains. I'm all for making things yourself, but I'd recommend just buying from Motordyne on this one.

 

Buy an used spacer in the classifieds. Way more cost efficent.

 

AS far as the cleaners, yes, give them a shot. But it might take mulitple doses to do anything. I thought about recommending an engine flush (a more harsh procedure) but I decided against it. If it's indeed a sticky lifter, it's going to take some time for the varnish (or whatever) to gently get cleaned off. But I'd say, if the rest of the valvetrain is clean, I don't know why this particular lifter would be stuck but one never knows.

 

How can you determine it's not? The reason why yours have a tick is because aftermarket cams are known to do this if you don't shim them right. And you have the benefit of having before/after results.

This gentleman is on stock cams. So whether or not he actually has a valve tick or not is not really the issue.

You also offered up your video from last year to the OP's related question in 08'.

 

Changed the oil, added MOA. Added 44k and had The BG Fuel Injection System Cleaner shot in this morning. Just got done changing the plugs and cleaned up the K&N. I'm going to head to Florida (900 miles each way) for the long weekend, I'll get on tomorrow and let you guys know if the noise improves or gets worse. I'm interested to see if MPG gets better too.

Have a great long weekend! Hopefully all of you get one...

 

Good luck. Maybe a good long drive will help clean things out.

 

 

I havent heard of this... This could be it! I'll investigate the manual and look into it! Thanks!

 

Why they make inexpensive automotive stethoscope with various probes to pin down the source of noise.

Shimmed cam lifters have been a godsend to Dealer Techs. It does take a full day 10 shop hours to do it right and spot on....................assumming you have MULTIPLES of every 27 step shim in stock.

As a Specialty Independent we have to measure them, then call around the 5 dealers in ATL to find the EXACT values we need. It never fails that we need to get parts from 2-3 dealers as they are always out of some values.
We charge $1000 + shims and parts cost usually recommend a spark plug change since easy and cheap with things exposed.

Important to do the math exactly to correspond for local temperature variances. Hot vs Cold selection.