I've been having this issue for a few weeks now, it seems to be slowly getting worse. It feels like a certian narrow airflow range seems to trigger a CEL which only stays lit during certian RPM ranges. I took a DSMlink datalog and something tells me there is something up with the knock sensor, here are a couple screen captures.
This is when the CEL was on during closed loop operation. As you can see the ECU is clearly pulling timing which is very noticable as a power loss. I'm guessing it's pulling timing because it's seeing knock, but I can't figure out where the knock is coming from. The oxygen sensor seems to be working fine.
For a short time during the 3rd gear pull, where the white marker is, the CEL was on.
The weird thing is that the CEL doesn't stay lit. When I try to get the DTC's nothing shows up. I am running a completely stock engine, except for a hacked MAF and an EVO exhaust manifold which was a replacement for the cracked/leaky stock manifold. All of the settings for the DSMlink are zero'ed out.
