So about 9 months ago this problem started when the intake was taken off my car to access my headlights. After everything was completed with the headlight install. I went to out to drive and suddenly noticed what felt like a misfire and after 3000 rpm in each gear it doesn't exactly bog But instead feels like I'm flooring it in a prius. Their is no difference of acceleration between the pedal half way down and press all the way. Replaced MAF, spark plugs, coil packs, tested wires from AIT and still having the same problem. Left with injectors fuel pump entire electric harnessing for coil packs or the "igniter" which is called something different. No check engine light. Used to only run like this if it was colder than 67-70 degrees outside but after the new coil packs it runs shitty no matter what the temp outside is. Occasionally it'll accelerate how it's supposed to but only if you floor it in every gear starting with 1st. Everything replaced is all OEM.

 

Welcome to the board- it would help to know what year Z you have and how many miles. Also, do you have any current codes showing after your drivability problems started?

 

It is a 2003 track. 106k miles. It did throw up a MAF sensor code once but I replaced it and it never came up again. Other than that nothing.

 

It sounds like it continues to have problems reading the MAF. Certainly doesn't sound like a misfire. But trying to do diagnostics over the internet is an iffy proposition at best- have you taken it into a qualified Nissan tech with access to a CONSULT III?