Okay this will be as short as possible. The car has been great for the year i had it. Air and fuel filters changed recently. ITs a 5spd and has 136000 miles on it. Has a VE30de engine in it.

Okay about a week ago the engine ran weird, I tanked up in jersey 93 octane Mobil and as I was driving out the car was shaking, the engine was shaking. I drive for about a min and the problem disappears. Next day I do some driving and I stop off somewhere and start up the car like 10 min later. The same thing happens, the engine shakes and runs rough when i drive. I put it in neutral and rev the engine and its not smooth and it shakes. I pull over and check whats going on. Like a min of driving and its gone. So I went out and bought new ngk plugs for my car and installed them. The problem didnt go away so i tried gas treatments and problem is still here after using all my gas and tanking elsewhere. Any advice??? Just on monday I drove up to buffalo from nyc and it ran fine geting like 28 or 29 miles a gallon.

 

On Monday, the car did not run rough at all? That sounds very difficult to diagnose. I have not come across this problem with my VE30DE, but the only thing that comes to my mind first, is if the throttle body is getting gummed up. I'm not too sure, could be way off, but it's something to think about.

Good luck...hope you figure it out.

 

Your injectors may be clogged as well, (always try the simple things first), at your next fill up put in a bottle of fuel system cleaner, (i prefer techron), I run one of these once a year and it really smooths out the engine.

 

After the car runs for a min or 2 the problem is completly gone, I can drive for hours or mins and it runs fine. Then i turn it off and wait like 10 min and turn it back on it runs rough again till i start driving it again.

 

Next time it runs bad try removing/unplugging the coil packs one at a time. If all make the car run the same then you know either all packs are bad or there is a problem somewhere else. However if one cylinder runs worse or has no effect on how the engine runs then that leaves fuel injector or coil pack.

 

injector and throttle problems can be pretty random as for when they show their ugly faces.

 

Quick question the coil packs are those things connected to the spark plugs right?? And if i disconnect one at a time then wouldnt it make one not spark anyway causing the engine to run wrong? I'm not sure how to go about and know which one would be causing the problem. IF you can then explain more on what to look for. Thanx for the advice

 

Roughness in neutral i would guess is one of the cylinders is misfiring. Since it is random I would check your injector plug contacts for corrosion. It could be barely making contact and sometimes loses contact completely. Wiggle the injector harnesses and see if you can reproduce the symptom youve described. Mine were green from corrosion so I cleaned them up with a metal pick. If that doesnt help do a resistance test.

 

Well I was playing with the ignition coils and my friend said maybe its a valve problem, because the car makes this noise from the front passenger side of the engine when i rev it and goes away in a couple mins after the car is running and it doesnt come back. Can this be it?

 

The next time you change your oil/filter, do a motor flush, like STP or Gunk. It will help free up any sticking lifters/valves, also it will clean out the oil pressure regulator.


If your ignition coils are original, I would reccomend replacing them (all 6). You can get them from courtesynissan.com for around $50 a piece.