Another phantom knock thread...

[Spoolin92GSX]

Alright, I've been reading, searching, and trying all the ideas I found for the past week and I've reached a dead end trying to figure out this damn phantom knock.


Mod list in profile is up to date, OEM Mitsu sensor is only a couple months old, wiring is in good shape, running 2g timing map with a little less timing in lower load cells, healthy AFRs, intake manifold is tight, "Y" bracket is tight, there's nothing physically rattling/loose that I've been able to find..

Now, something interesting to note is that it only acts up after being at operating temperature, and at that point the car becomes almost impossible to drive. I'm not sure what could affect/induce phantom knock based on temperature.. Often times, it will start "knocking" as low as 1000rpms and 20% throttle - I can let off the gas, let the knock count settle, and get right back on it and it'll be fine. WTF

I can post a log if requested, but it will be in TunerProRT. Thanks in advance guys, this is driving me nuts!!

By the way, when it does "knock" it will stay pegged at 43 counts and not go down until I let off the throttle.

 

[xxNocturnalxx]

The timing pulled from knock usually stays until you let off, that's normal. I had that same thing in my 1g GSX all the time it never bothered me though because it rarely happened when I was actually racing, high rpm and boost. The high load at low rpms has a lot to do with it.

 

[Spoolin92GSX]

See, that's the thing: the "knock" stays too. And when I mentioned 1000rpms that's in first gear, I'm always mindful not to lug the engine in higher gears. It'll start at any point, even cruising on the freeway, say 4000rpms in 4th to pass a truck, well before I even build any boost pressure (ie as soon as my foot touches the throttle).

 

[counti41]

I have the same issue but i beleive its due to vibration, which can trigger the knock sensor, I'm thinking of getting a new harmonic balancer or a fluidampr, which would cancel out the engine vibrations and hopefully stop the phantom knocl hopefully.

 

[xxNocturnalxx]

See, that's the thing: the "knock" stays too. And when I mentioned 1000rpms that's in first gear, I'm always mindful not to lug the engine in higher gears. It'll start at any point, even cruising on the freeway, say 4000rpms in 4th to pass a truck, well before I even build any boost pressure (ie as soon as my foot touches the throttle).

Thats kinda what I meant, knock stays too until let off.

I hope find your issue though, I never did find mine

 

[Spoolin92GSX]

Forgot to mention harmonic dampener is new also . Nocturnal OK, I missed that part I'm almost thinking I might have messed something up in my EPROM code, I'm going to try from scratch today and see if that does any good..

 

[Spoolin92GSX]

Alright, went through my entire tune and started from scratch and it's exactly the same. Kind of leaning towards an exhaust leak as I know I have at least one, but the leak is only audible after a cold start Oh well, gives me an excuse to port my o2 housing