2002 i35, Bucks, Jerking, loss of power in top end of rpm band + rattle noise under moderate accel

[Hdnseek]

*I have spent hours searching prior threads but to no avail i have not found a definite answer or suggestion to these conditions*

So i have a 02 i35 that i picked up with front end damage for 300, runs and drives, has 135K on it.
It sat for 8 months or longer before i saved it from going to a junk yard.
The frome is straightened and i welded a new front radiator support in, and in the process of finishing it up to use as a dd.

Here are the issues im having:
- I have been getting a unbarable jerking/bucking problem when i go WOT right aroung and after 3800rpm. I can punch it in first and itll pull to right at 4k strong then the power band falls off but itll rev out to redline, after it shifts into second at 4500k it starts bucking hard like im hitting fuel cut. It has started doing it in first gear slightly to around 4k. Anytime i want to punch it it has no power and rattles my teeth from the jerking. Sometimes it clears up a bit but still lacks power up high.

-Under moderate load under 3k i get what sounds like chain slapping, it goes away after it downshifts or revs past 3k, assuming im starting to get into timing chain problems but hopefuly not.

- The car idles perfect, no check engine lights, only stored code is a power steering circuit fault. Cruising is perfect, drives like new until i hit 4k and sometimes itll buck slightly when cruising.
-Going to do somemore diagnosing tonight to check mounts, maf, tps. I just flushed the trans and the problem remains persistant.

-Any suggestions to problems you have came across similar to mine please let me know. Just getting frustrated the more i dig into it.

Thanks in advance

[boost_boy]

My 02 Maxima is experiencing this same problem. Did you ever get it squared away?

[NutriaforBreakfast]

The only time I had some slipping/jerking was when i had a bad cv axle

[03maxmuff]

Maybe clogged converters. Is there an eggy smell during heavy acceleration? That's usually a good sign that the converters are on their way out!

[ef9]

Possibly your MAF needs to get the wires re-soldered (inside of the unit).

[boost_boy]

I have changed AFMs, new pre-cats and main cat, new ecu, new injectors, new fuel pressure regulator and dampeners, removed cat-back from main converter, new pedal sensor and lastly, I just replaced my old (refreshened) motor with a 2008 VQ35 with 74K and this thing still lacks the upper rpm power that it is known for producing, once upon a time. I even changed the air cleaner box and am using the 2008 intake manifold. No codes and the car drives like normal until it hit the performance band and it does nothing special, but just drives. Any more ideas from anyone that can help us with this issue? I'm still working on a cure, but if I find out before anyone chimes in, I'll be sure and share.

[Fezzik]

cam sensor?

[Hdnseek]

Changed out rear motor mount that was shot and replace the maf with new unit, still doing it. It'll pull fine to 3800 then just starts jerking while still trying to rev to redline and will shift hard around 5000. Going to check the rest of the mounts on the sides tomorrow. No egg smell just frustrating!!!

[Masaker514]

cam sensor?

x2 on this i was having a similar problem changed out both my cam sensors, bank a, bank b and it ran amazing. I wouldn't buy any auto parts replacements, stick to oem dealer only.

[Hdnseek]

I fixed the jerking and studdering at high rpm. I went to clean the throttle body and found that the intake rubber duct had torn on the bottom side and was letting in a while bunch of unmetered air. Runs better but stuffers bad when first start up after sitting over night and dies out some Times when intially cold. Did you have any check engine light

[Cedric6581]

Have the transmission checked, sometimes the gears would get messed up specially on front whell drives.

[NutriaforBreakfast]

Are there any noises from a cold start up in the am?

[Hdnseek]

I'll post a very video, I fixed the jerking, the intake tube after the tube was torn underneath and letting unmetered air in. However I'm getting such an erratic idle and it'll stall out when it's cold. Any starts after it warms up its fine. Also I have been getting a suspension knocking noise and I've put it in the air and shook everything down and can't figure it out. I'll post a video