I truly apologize if this has been covered in here somewhere already, but I looked through these forums and found similar issues, but none that were quite the same.

A while back my car (03 z) started shaking really bad. I tried diagnosing it and fixing what I could to get it to stop, but nothing helped.

I found oil in my 6th plug spot so I replaced the valve cover gasket, that didn't fix it. I changed all my spark plugs, and one of my ignition coils that seemed to be putting out a weak spark, and its still shaking.

I replaced my tranny mount, and am about to try replacing my motor mounts, but I want to see if anyone here can offer any helpful ideas.

Basically, I've only owned the car about a year or so. And I've had to replace the alternator along with this issue. (Don't think that would contribute to my current problem, but maybe it will spark something in one of your heads and give me a solution?)

So as stated, my car shakes very violently all the time. While it's idling it shakes very very badly, which originally made me think misfire, but I'm getting no codes at all. And then I thought vacuum leak, but that would go away under acceleration I believe, but the shake only gets worse when my rpms go up.

I've been trying to figure this out for like 6 months now so any help would be awesome

 

My first guess would be motor mounts ... that is what I would check carefully first.

 

OK, now I'm not an expert mechanic, and havent ever dealt with motor mounts before.

So is there an easy way to check them in my driveway? Like maybe jack up the engine and watch the mounts as I do?

 

OK, here's a quick update. The ignition coil I just replaced (in which I also put in a {2nd} new spark plug). Still for some reason isn't sparking. I pulled it out, and the spark plug looks brand new (still shiny like straight out of the box, no black residue or anything that would indicate any spark or explosion of any sort)

 

If you have a multimeter you can check the coil plug for voltage. If you are getting voltage and it still doesn't fire, its most likely the coil pack.

 

OK, and what if I am not getting voltage from the wires that go to the coil pack?
My assumptions for the problem now are whatever supplies the voltage to the coil pack malfunctioning, or maybe my fuel injector for that cylinder not working.

 

If you arent seeing voltage there is a problem in the wiring most likely. Youll need to trace back to find any issues with the wiring. That will have nothing to do with the fuel injector though. If the plug isnt firing, its either the coil pack or the connector not getting the voltage.

 

If you're going to work on your car, get the right tools so that you a) don't waste money on things you don't need and b) don't make a bad situation worse.

This is a very simple tool to see if your coil pack is firing:


If you don't already have one, get a scan tool with live data (get a decent one - it'll pay for itself quickly):


A two-channel (or better yet, a four-channel) automotive scope is the best tool you can use to make a proper diagnosis, as long as you take the time to learn how to use one. (see the scannerdanner channel on youtube for a quick education). Go with a used on one ebay if you're not doing this for a living. Otherwise, get the best one you can afford.

There are so many more things you can get to make diagnosis simpler. I have a roller box with nothing but diagnostic tools on it. Since your car isn't throwing the MIL (idiot light), then it's probably not an ECM issue. It'd be throwing codes if you had a severe enough misfire to be noticeable. Your problem is most likely with the engine mounts. Stick with the FSM procedures when replacing them (you can get hurt if you take shortcuts). Also, make sure you have the right hand tools and/or air tools and safety equipment before you start working on it.

You can examine the mounts quickly using a borescope. This is the one I have (and highly recommend).


Good luck.

 

OK, so another update. Checked my ignition coils and they are all fine. Cleaned out the one cylinders fuel injector, and everything seems fine on all fronts. I've also looked at my engine mounts when the engine is revved, and I don't see any drastic moving like I've seen engines do on YouTube when their engine mounts are bad.

So essentially now I'm at a complete loss and have no clue

 

If this is an automatic and it shakes in D while idling, it's guaranteed to be motor mounts.

 

No, its a manual.

 

Did you check your axle? Give it a shake to make sure it's not loose. Just goin' down the list. Like I said, if you're not throwing a code, it's probably a mechanical issue, not an ignition or fuel one.

 

Check both camshaft solenoids.

 

So I broke down and took it to a couple mechanics. One says the crank inside the engine is ****ing up thus the engine is bad another thinks its the clutch.

So I'm not sure which one, but if anyone knows of any ridiculously cheap vq35de engines for sale I mau be interested haha.

(Side note its at a Nissan dealership now for an hour diagnostic, which most likely won't yield results since they are purely motivated by money)

 

OK, so another update.

Crank seems fine, so the Nissan techs are thinking its something in the clutch area (clutch, flywheel, something along those lines).

So now my question is, does anyone have any experience in replacing those items on these cars? (I've heard it said that they are pretty unique and unlike other clutches).

So I'm gonna work on that front, and I will search the forums for a thread on those topics so as not to get in trouble with the admins on here haha.

Thanks again for all your guys' help and headings