Hello, I have a 2003 Infiniti G35 4 door. 225600 miles. ON body/tranny
New(er) motor that has 167k.
Power Mods-
-Cold intake.
-Test pipes to full Z1 catback.
--
STOCK everything else.
Now as of last month I attempted to put in a 5/16 spacer, I had to work the same day so I rushed it. As I installed it I started the car and it was running sloshey and lean. I took off the spacer and it sounded okay. I went for a drive and when I put my foot down(operating temp) it stays in the gear it is and shifts at 3 to 4k. When I gas it from 0mph It goes slowly then shifts at 3 to 4k and goes to how ever fast I let it go. Before the spacer I had the (nightmare transmission code) forgot the number and a knock sensor code. The next day I took all day to carefully replace the knock sensor. I replaced it clean the injectors etc. Code cleared but same lack of power problem. My trans shifts hard within the first 20 min of driving( I know my tranny is bad I got a brand used one on the way). Im wondering what it could be. My tranny? Seems like nobody else has had this problem. I do have catallac engine codes due to my cat delete. I'm worried my new trans wont fix it. SO what can I do. I HAVE put in a New throttle body, MAFS, Replaced the EVAC control thing, Looked through the EVAP system, Oil change, Tranny fluid is red and at fill line(checked after a drive of the car) Took my whole plenum off (top part and bottom part the connects to the top of motor) and replaced it. Still power lost. Next is going to be the tranny but just worried it won't fix it.

 

Exactly what codes is it throwing, are you sure you didn't get the coil pack harness wires mixed up it's VERY easy to do. Did you unplug the throttle body, if so you MUST DO THE RECALIBRATION.

I'm betting you didn't recalibrate the throttle body, check the FSM section EC - Engine Controls at the beginning of the document under "basic service procedures".

 

Thanks for the reply, When I took the plemton off I DID NOT do the recalibration of my TB. I had no idea I have to do that every time I unplug it. As of the day of the post I pulled the spark plugs from the passenger side of the bay, The cylinder closet to the firewall was soaked in oil, The 2nd one a little bit in oil, the one closet to the front of the car was dry. My value body was leaking oil so i replaced the gasket but same power issues, When going for a ride and I step on it it doesn't downshift automatically I have to manual downshift with the slap shift, When I do it slowing climbs and starts misfiring and sounding like 2 step. My 3 engine codes all have to do with the word "circuit" in the name and 2 have to do with my cats(I have test pipes so I thought that was normal to have 02 sensor codes) The 3rd code says something about heater circuit, Im currently getting ready for work Ill back to respond at around 9pm est