Hey guys,
I just got a quick question in regards to a knocking issue on my car. The car is basically a 25DE+T with std turbo, injectors, fmic, and powerfc and a few other bits and pieces. It's currently running 10psi and have been running for the past month with no problem. Anyway, in that month, I've pretty much been taking it quite easy on the engine. I tried to look for the problems and whatnot in that period before I went full bore with it.
So last week, I started to push the engine a little bit more and more. I started with going full throttle in 3rd gear and that gave me no problem whatsover. The car pulled hard and everything is still good. However, 2 nights ago, I tried to push it in 2nd gear and I got the engine light flashing. First I did this at 100% throttle, and then 80% throttle. Now, I will take it back to the tuner to get it fixed, but before then, I want to get a little bit more knowledge as to what could be the main cause. Here's a jist of my thinking:
The knock sensor started going off around 4000-5000RPM all the way to redline. This is to would suggest
(1) It's not a boost spike because I don't think boost "spike" would go for 2000RPM long. Or could it???
(2) It's more likely to be an issue with timing because, if I'm not mistaken, 4000-5000RPM is where advanced timing usually kicks in from the VVT.
So what do you guys think? Is that a fair assessment of the issue? or can a boost spike really occur for over 2000RPM? Is it even possible for the advanced timing to affect the 2nd gear that much more than 3rd gear to cause a knock in 2nd but not 3rd gear?
I do apologise for my noobness in tuning but it's something I really want to learn. So thanks for all your help guys. Much appreciated.
NOTE: I don't have the handheld for the PFC.