gidz

so my tuner hooked up my knock sensor to my check light so recently i installed a sparktech ignition system and did over my intercooler pipes... but my problem is that when i am driving at times the light will give me a few blinks while the car is going into boost... can you tell me what that means?

C6C6CH3vo

iTrader: (9)

Knock sensing is not a perfect instrument. It is quantitative, only a certain percent of it's report on knock is actually knock. It's accuracy get's worse with addition to aftermarket parts too.

To be safe all you can do is consider all knock sensor activity at high cyl pressures (high boost, load) as real. And ignore the rest if it's occasional and not chronic

Raptord

iTrader: (10)

Log the car and see if it appears to be real knock or not. Trying higher octane fuel is a way to check if the knock is real; if it still flashes with a higher octane gas, it may just be phantom knock.

Also check your engine bay to make sure you new pipes aren't hitting against anything metal.

evo420

I have this same issue, only knocks while building boost. But I'm on a built motor. Relly sux!

gidz

Well guys my motor is also built... My tuner said that I need to retune so I gonna try that and see... But tell me something guys Ive got a built motor that consist of forged pistons, rods,272/272 cams Garrett gt35r turbo etc. Can u guys tell me how much HP I can get out of this running stock ecu flash?

philr8

iTrader: (4)

How longs a piece of string LOL

What a silly question mate, all comes down to tuner, fuel, motor, temps etc.

Blitz

iTrader: (11)

Bumping this instead of making a new thread.

In the process of getting tuned remotely and I have encountered the same issue as the OP. Logs sporadically show anywhere from 1-4 counts of knock on spoolup at partial throttle between 3000-5000 rpm. Doesn't happen every time but with the CEL set to flash at only 3 counts of knock I am seeing it flash pretty often just driving around town.

Let the tank go almost empty today and put in a few gallons of 100 octane. Still getting the same knock at spoolup/partial throttle. This pretty much confirms it is phantom knock, right? Because otherwise the 100 octane seemed to completely fix the knock I was seeing at 6500+ rpm at WOT on my old map. So that knock was real, this doesn't seem to be.

I understand the knock sensor can be adjusted via the tune and my tuner has suggested that as the next step. Good move or no? Like I said the knock is sporadic and doesn't seem to occur beyond 5000 rpm. I am worried about messing with the knock sensor because I've read here that Mitsu did a good job calibrating it and it is not wise to mess with such a sound safety feature.

And yes, I have looked for whatever could be banging around. No luck.

Raptord

iTrader: (10)

If 100 oct. gas didn't change anything, it should be safe to say that it's phantom knock, and you should not have any problems with adjusting the knock sensor sensitivity to get rid of it. I would agree with your tuner. Some small adjustments to the background noise multiplier table should get rid of your phantom knock while keeping the sensor effective in the event that you get real knock.

ianVIII

You also need to understand that built motors are usually a little more noisy and if your on a stock ecu, it may have problems reading or identifying or even adjusting to the noise a built motor makes. And when i say noisy I just mean they produce different sounds then your stock motor setup. Correct me if im wrong?

Raptord

iTrader: (10)

Yes, changing internals in an engine can change the harmonics produced by the engine, and can potentially lead to the new sounds being picked up as knock by the sensor.