EightySix Four
Diamond Member
So I've been working on cleaning up my tune for a while on my car with HPTuners software. I'm running 22+ psi from the turbo and have plenty of fuel and such. I have new parts to install in the motor (rods and pistons) but I'm leaving for China soon and that is second on my list. I've been running into a problem while tuning though. I've been getting knock (ping/detonation) while on the throttle.
My initial fix was to work on dialing in the MAF. By making the MAF as accurate as possible, the computer would know how much fuel to use without having to compensate after the fact based on the wideband O2 sensor. (narrowband O2 sensors can only tell if the car is running stoich or not, wideband can give you the exact AFRs). With some help from Shabby, my MAF was narrowed in with .5% throughout the whole rev range but I still had knock.
I knew the car could handle what I was asking of it, others are running more timing and boost on 93 octane and it had become very frustrating. So I continued to look through the my logs in hopes of something jumping out at me.
As I was browsing through old log files, I noticed a distinct time period when the KR became worse, and after looking closer I noticed that after that time my IAT's didn't seem to be in line with the ambient temperature, and often my IAT2s (temperature after the intercooler) were hotter than the IATs (pre-intercooler). I decided to put the car up on the lift and see if there was something blocking airflow to my intercooler or if it was damaged somehow.
This is what my intercooler looked like (stock below for reference):
That isn't my picture, I stole it from another forum where people have had similar problems. There was a bad batch of intercoolers from the factory and certain Kappa cars have bulging/ballooning under even normal boost. The 22psi I had been running apparently accelerated the process and mine was even larger/worse than that picture. Had the IC replaced under warranty (there is a service bulletin) and then ordered an aftermarket one to replace it with.
Moral of the story: Cars are still hardware, look there first 😛
My initial fix was to work on dialing in the MAF. By making the MAF as accurate as possible, the computer would know how much fuel to use without having to compensate after the fact based on the wideband O2 sensor. (narrowband O2 sensors can only tell if the car is running stoich or not, wideband can give you the exact AFRs). With some help from Shabby, my MAF was narrowed in with .5% throughout the whole rev range but I still had knock.
I knew the car could handle what I was asking of it, others are running more timing and boost on 93 octane and it had become very frustrating. So I continued to look through the my logs in hopes of something jumping out at me.
As I was browsing through old log files, I noticed a distinct time period when the KR became worse, and after looking closer I noticed that after that time my IAT's didn't seem to be in line with the ambient temperature, and often my IAT2s (temperature after the intercooler) were hotter than the IATs (pre-intercooler). I decided to put the car up on the lift and see if there was something blocking airflow to my intercooler or if it was damaged somehow.
This is what my intercooler looked like (stock below for reference):
That isn't my picture, I stole it from another forum where people have had similar problems. There was a bad batch of intercoolers from the factory and certain Kappa cars have bulging/ballooning under even normal boost. The 22psi I had been running apparently accelerated the process and mine was even larger/worse than that picture. Had the IC replaced under warranty (there is a service bulletin) and then ordered an aftermarket one to replace it with.
Moral of the story: Cars are still hardware, look there first 😛
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