Seijuro

Logged this driving home today.



36 counts of knock!?

I don't know how this could be real knock, but I also don't know how this could be phantom knock. I'm not even sure what to do with this. Load is low, throttle is moderate. RPMs (you can't see in this picture) are at 2600. Fuel control is still closed loop. This is in 3rd gear.

You can see 1st and 2nd gear, where there was more throttle, more load (and more RPM), and the same fuel, with a count or two of knock and a slight amount of off-throttle knock coming out of 2nd.

Does anybody else ever see anything like this? I'm at a loss as to how to react.

TTP Engineering

iTrader: (465)

What kind of car? You either have a bad sensor, phantom knock or a blown headgasket.

Seijuro

91 eagle talon. I don't have any other blown headgasket symptoms but I had no idea it could cause this, that's a good one to note.

I didn't know phantom knock could spike like though, I thought it would only account for a few points of knock here and there that weren't real.

eag36

iTrader: (2)

phantom knock is actually known for producing those high spikes

hediki12

did you ever change your knock multiplier low and mid?

Seijuro

No I haven't touched the knock settings at all. There's been so much other stuff to look at I haven't gotten to it yet

I also did not know that phantom knock is known to spike to a ridiculous knock count. I guess it's time to read up on adjusting the knock stuff.

hediki12

ok change low knock multiplier to 17 and mid to 21 that should fix it.. its very common when we do the swap. or you can go and buy a evo 8 knock sensor and leave the multiplier as is.

VIIIrs

iTrader: (5)

Man i had the same exact problem and i cant remember for the life of me right now what it was. Let me think on it for a bit and get back to you.

Seijuro

Oh is that for a 1g DSM knock sensor? I have a 2g knock sensor which is functionally identical to the evo 8 from my understanding.

VIIIrs

iTrader: (5)

shouldn't matter all a knock sensor is, is a microphone.

hediki12

yes this is for the 2g as well... ive had both 1g and 2g knock sensors.. the 2g is simular but not identical to the evo8...
and yes they are all microphones but it does matter ..there thresholds are difrent based on motor specs and a butch of math i dont understand.....
if like proff go o the dsmuners.com article on the ecu swap and you will see....

VIIIrs

iTrader: (5)

yeah but doesn't the ecu tell the knock sensor what is actually knock and what frequencies and how much is actually knock.

hediki12

yea but each knock sensor isnt the same... they function the same... but there not the same. thats like saying all mics are the same and you can make album quality music over your iphone and the producer will fix it...

0xDEAD

iTrader: (3)

He doesen't want to be doing that on the 2g knock sensor.

OP, I've actually made high boost passes on the evo 8 ecu. Keep the stock knock settings, trust me, they are fine for your setup.

0xDEAD

iTrader: (3)

You need to be a little more careful when putting out "information". If this rumor sticks it could very well start costing people motors. The 1g is vastly different from the 2g and the 2g is different from the USDM evo 8 knock sensor. Just run the correct knock sensor. Its cheap and most need replaced anyhow.