Hey Folks.

I'm from New Zealand where the G37 is listed as a V36 Nissan Skyline, practically same cars aside from the translation, anyway I was hoping someone could shed some light on my issue

My Relevant Car Info:
-06 V36 Skyline VQ35HR
-Test Pipes
-Stillen long pipe intake
-Tuned with UpRev

The Issue:

1. Always under low throttle at the 3,000 - 3,200RPM range the car will misfire and shudder
2. This occurs intermittently at medium to high throttle
3. Only at this rev range (3,000-3,200RPM)
4. Full throttle has no issues
5. Makes no difference the gear
6. Notable hum/bog sound from exhaust prior to this occuring between 2000-3000 depending on throttle/accelerator position.
7. The only thing that has happened since I've had it tuned is repainted the calipers and its been running fine...well semi-unhappy with tune but fine for the past few months.
8. Video of said issue

What I've tried:

• Checked Throttle Bodies and cleaned
• Checked sufficient voltage is at the throttle bodies
• Checked plugs and coils
• Checked for exhaust leaks
• Checked intake and cleaned MAF & Pod Filters
• Checked MAF Voltage
• Checked Accelerator pedal position
• Had ECU scanned which originally returned codes such as throttle position sensor/accelerator position sensor, now its returning U1000 CAN bus communication/steer-ing wheel lock control unit/Signal: vehicle speed/Supply voltage/Select lever position/clutch switch PN signal/Steering column lock relay/ignition circuit monitoring relay/steering-wheel lock control unit. Most of these codes are irrelevant and most likely related to the aftermarket alarm/other electrical **** that's been done.

A fellow is going to go over a few other minor things tomorrow just to double check if he can find anything, the original tuners put it down to possibly being the transmission however this doesn't explain why it only happens at this rev range nor why there aren't other issues. It's been said that its definitely a tune related issue although how can a tune pop out?

Any further ideas or things to check would be greatly appreciated.

 

What happens if you put back the stock tune?
If it runs fine, then you know the mechanicals/sensors/wires are OK and it IS the tune.

Data log the accelerator pedal, both MAFs, both throttle position, injector pulse width, and AFR bank1/2.
Then, go for a short test drive: one with light throttle to recored the issue, then at full throttle.
Look at the data logs and see if anything stands out.
-OR- post the data logs here.

 

Had a shop tune this, sounds like it should go back to them once again to sort out or is there a method that I can use with OBD2?

 

DId you ever find out what it was? My car is doing the same except around 2k rpm mark. Cheerz

 

Trying to post in a three year old thread won't get many answers. Why don't you try starting a new thread with some specifics on YOUR car?

Include some specifics like how many miles are on your G? How long have you owned it, and when did the misfire begin?

 

i know man, i tried making my own thread but got no answers, its been weeks im trying to figure out what my issue is but no one seems to know. :/