S13 SR20 hitting a weird limit.

[Kevin Tyler]

Never once have I experienced an issue like this before. Real quick a run down of the hardware. 

s13 sr20det running e85 on a gt2871 Link g4+ drop in. 

Problem is under full load, the engine will encounter a break up around 5000 rpm. Will drive all the way to redline not under 100% throttle. I have gone through logs and files and nothing is out of the ordinary. I am chasing my tail on this one. I have replaced every sensor I can. new lift and surge tank pumps. I have removed the boost solenoid and plumped to run mechanical spring pressure in the waste gate with no change. I have also reduced boost levels with no change. The more I try to drive through the problem, the lower the problem occurs in the rpm range until the car has virtually no throttle input. I have attached a log and cal file if you want to take a look at them. Im lost at this point. The ignition system is z33 coils with plugs gapped to 0.56mm/0.022 for what its worth. 

 

log 9-20-21-1.llg Tune 9-20-21.pclr

[Adamw]

Where was it misfiring in the log - on the second pull?  I dont see anything obvious in the log, from an ecu perspective it looks happy, trigger looks ok.  Are the coils genuine Nissan?  Have you checked the lambda with some other device?

[Kevin Tyler]

Thank you Adam for replying.

Yes they are genuine vq35 coils. I have sourced a new set and will try again later today with another new set of plugs. New Bosch 4.9 is in and calibrated. I believe its a hardware problem at this point. I will try a known good wideband controller next as well.

Missfire starts roughly at 5000rpm maybe a bit lower, basically when mgp reads 18+psi