Missfire possibilities? [94 Q45]

[SavageNerdz]

Well, as i approach the end of my Q ownership, i'm faced with trying not to screw over the next poor person who buys it. With this being said, currently it appears to be miss firing. This is the primary issue and my main concern at the moment.

Definitely got some vacuum leaks, however this shouldn't to my knowledge make an engine misfire, at least not as badly as this one is in any case. Car seems to be in limp mode, however i can't be for certain on that one as if is misfiring that would account for the loss of power/acceleration.

Notable Symptoms: Can barely notice the misfire in P/N, but the it idles at roughly 1000-1050 when in P/N, in D, R, 1, 2, 3 It idles roughly 750ish or what most of us consider to be normal. However, with the car being in gear this would put load on the motor, even i'm not moving (if i'm wrong let me know) and the misfire becomes MUCH more noticeable. The car drives okay, and the loss of power is definitely more noticeable in the lower portion of the power band. In the higher portion of the power band the car accelerates quite well and honestly pulls pretty freaking hard.. This has only added to my confusion as i would expect the power loss to be fairly static, not so dynamic.

If this were my tiburon i would know where to start, however with Nissan/Infiniti's ways of doing things it is VERY intimidating looking into the bay of my Q45. My first suspect is knock sensors, however wouldn't the knock sensors cause the car to jerk? The other theory i currently have is the fuel pump/filter, in the past the car had some work done to it. Valve cover Gaskets have been replaced, fuel injectors were replaced as well, so it narrows it down... somewhat. I did manage to find the KS on amazon for about $35 ea, so they're not going to break the bank. However, given the fact that the car does pull quite hard in the higher power band, would that cancel out my theory on the fuel system? Logically it should require even more fuel at WOT, and hence i would think that if there were a failing pump or clogged filter it SHOULD be even more noticeable when the amount of fuel needed is increased.

Thanks for any and all help,

Lane

[94Q45Beast]

pull codes as a place to start. the CEL won't illuminate most of the time when there's a trouble code.

[goody90q45]

If you replaced the fuel injectors with remanufactured FI then they could be failing also. It takes about 5 minutes to check both the FI and KS with a voltmeter. Connectors are located on the passenger side of the engine. Let us know the readings you get.