shiftzimportz

my 04 z has about 79k miles recently i noticed that its very laggy rpms are struggling to move alltogether car falls flat on its face i changed the knock sensor and i have read the other post about other users but cant find out what solved there problem i called everything nissan and they said only 03 models have the sub harness for the knock sensor and 04 up its tied into the main harness which nissan wants 800+ for any ideas i would appreciate it greatly the z is 6spd and has injen coldair intake test pipes and x02 exhaust
and i can drive lol if you can text i would appreciate anytime is fine 386-561-1735 sorry if i posted incorrectly its my first time


thanks in advanced

Dr. Venture

iTrader: (19)

why would you assume it was a knock sensor? Nissans always have "knock sensor" ghost codes regardless.

Perhaps you need the MAF sensor due to the CAI it may have gotten h20 inside of it.


There is also a TSB on fuel system psi. Check into that.

shiftzimportz

idk reading other posts

shiftzimportz

i have taken it to nissan and did a diagnostic vacuum test and sensor check the car came back with no issues or known sensor failure also did a timing check and everything came back on spec i used my obd 2 to clear the code and the car felt completely different but it kept coming back i would clear it and it would work for a few days and come back now when i clear it it wont go away idk nissan also replaced the maf but it did no difference this was here before i installed the intake i actually purchased that intake thinking stock intake was chocking the car due to testpipes and exhaust but i was wrong

Dr. Venture

iTrader: (19)

I suggest you do a fuel psi test. at idle w/ vacuum the psi should be (kg/cm2) 51/3.7.

so 51 lbs.

check that and get back to us.