ECMlink Can't get rid of knock....

[Lolmooses]

Everything related to the questionnaire has all been verified to be good and in spec within the last week.

1g GSX 5spd running v2.5 of DSMlink

Mods:

Stock everything except 3" exhaust and walbro 190 that hasnt been rewired. 14b is running around 10-12psi om 91 oct pump gas.

I've tried pulling timing, pulling fuel, adding fuel. NOTHING is working. No matter what I do I keep getting knock when I start to spool and it just gets worse as I keep pulling. Brand new OEM knock sensor too. Im stumped....

Also, I cant get ISCPosition to 30. My BISS screw is maxed out and it idles weak at 750. I have to idle at 900 for it to be decent. Ive verified 4 times that I have absolutely no boost leaks thinking maybe thats what causing it, but now Im stumped on this as well.

 

[jakk220]

Are you sure that you are not getting phantom knock?

 

[Lolmooses]

I'm starting to think I am at this point. The only thing I can think of is my lifters being noisy that would be causing it.

 

[SNAKE_15]

I'm on my phone right now so I can't open the log, but have you increased the rpm and throttle position which will trigger the knock sensor once you pass what you set on those points?

 

[Lolmooses]

I have it set to 3000 and 20%. im worried I might damage the engine if I set it to ignore where I start knocking which would be 3500 rpm and 50% throttle. If my boostest is correct I start knocking at 4psi which sounds ridiculous to me. Thats barely anything.

 

[jakk220]

I currently cant view the log either, but if it is going up with the rpm then its probably more than likely phantom knock. Try making it so that the knock sensor reads all the time even under light throttle, and then just slowly increase the rpm while driving at like 20 percent throttle. if its doing the same thing it is most definitely phantom knock. But I am betting it is either way.

 

[Lolmooses]

I was looking through my old logs from July and I found some interesting bits of info. Timing and fuel sliders are 0'd out, running 10:1 or lower AFR and it was boosting 10psi at 50% throttle with 0 knock. The biggest difference was intake temp. My intake temps in my most recent logs have been over 100 degrees, sometimes as high as 126.In these old logs it was at 76 degrees....

Ive zerod out my fuel and timing tables last week and it still knocked just as bad with the same intake temps of 100+.

 

[Lolmooses]

Alright, with intake temps below 100*F and my sliders 0'd out Im still getting random spikes of knock that climb with rpm as I start hitting boost. I dont get any knock in 1st gear....Im stumped once again...

 

[Lolmooses]

I currently cant view the log either, but if it is going up with the rpm then its probably more than likely phantom knock. Try making it so that the knock sensor reads all the time even under light throttle, and then just slowly increase the rpm while driving at like 20 percent throttle. if its doing the same thing it is most definitely phantom knock. But I am betting it is either way.

When I had my knock sensor to read at all RPM and load it would knock consistently around 2500-3500 off boost, it just wasnt nearly as high counts as it is now when Im under boost at the same rpm range, so im guessing whatever is causing my phantom knock is creating even more noise under boost that the KS is picking up.

 

[bo0st]

Add 2 gallons of E85 to a half full tank and it should do the trick.

 

[Lolmooses]

If only we had e85 in Maine....

 

[Dxc545]

E85 won't solve your problems. Start from square one. Your biss shouldn't screwed in all the way and your idle needs dialed in. You can find videos at ecmlink.com

 

[Lolmooses]

I tried following those videos and I could not get my airflow/rev anywhere close to 0.25 because I cant decrease my global deadtime below 0 :/. My ISC being screwed in all the way baffles me. I dont understand why im at 19-22 ISCPosition at idle with it screwed all the way down. I know for a fact I have no boost leaks and its a new black ISC so Im out of ideas on that one.

 

[Dxc545]

If you don't have boost or vacuum leaks I'd check base timing and fuel pressure

 

[Lolmooses]

Base timing was set to 5* on the crank with a timing gun. Fuel pressure is ok.

 

[Lolmooses]

I was looking through previous logs and noticed this constant knocking at low boost started literally overnight after I did a WOT pull the day before it started. For it to just happen overnight means somethings really messed up and I doubt it has anything to do with the tune itself at this point.

 

[2gmitsueclipse]

If you are ruling out your tune, have you considered inspecting the knock sensor?

 

[Lolmooses]

I replaced it with a brand new OEM sensor a month ago. Ill check the torque on it today.

 

[Lolmooses]

Torqued the sensor to 17 ft/lbs and no change.Still knocks like a bastard. I was gonna try race fuel but after noticing that there are no unleaded race fuel pumps anywhere near me thats not an option anymore. I'm not paying $70+ for a can of race fuel that I only plan to use once. Seems like a waste.

 

[SNAKE_15]

Torqued the sensor to 17 ft/lbs and no change.Still knocks like a bastard. I was gonna try race fuel but after noticing that there are no unleaded race fuel pumps anywhere near me thats not an option anymore. I'm not paying $70+ for a can of race fuel that I only plan to use once. Seems like a waste.

Have you ruled out your fuel pump being bad? My car would knock right away when barely hitting boost. I added fuel and retarded timing with the same results. Ended up being a clogged fuel pump. Using race fuel is a bandaid fix for your problem so I wouldn't recommend it. For your isc problem, I would disconnect your battery for 10 min to reset your sensors. Then, your isc should start reading correctly. This worked for me when my isc read high.

 

[Lolmooses]

Fuel pump is a new Walbro 190 thats less than a year old :/. My battery was disconnected recently about a month ago for an entire day when it was getting some work done to it and its still reading too low.

 

[Dxc545]

You said it happen after a wot pull? A vacuum line could have come off. The ones behind the manifold are hard to see

 

[Lolmooses]

I did a boost leak test a week after that pull and everything was still in place with 0 leaks.

 

[jakk220]

Are you getting any other symptoms with the knock? like some sort of sputtering or weird ticking noises?

 

[jakk220]

Also one thing I have learned over the years is that new parts do not always mean working parts