fed up with knock control
Oct 16, 2008, 09:06 AM
#1
fed up with knock control
well the stock ecu is pissing me off to no end with phantom knock. Im really thinking about going AEM just for the knock control.
at low load/ vacuum if i rapidly press the accelerator i will get a knock spike of up to 18-20 sometimes, sometimes it wont knock (usually 50/50). the engine will also knock right around 3500 rpm no mater if im at 15 psi or in vacuum, at 20% TPS or 100% TPS. needless to say when this happens the timing pulled ruins the run. I saw this on the dyno and the difference between a clean run and a run with phantom knock was 430 whp vs. 380 whp. If i can get through the vacuum/boost transition and past 3500 rpm without knock the engine does no produce any knock, phantom or real.
I know this is phantom knock because it does this no matter how much timing is there, it also has the same behavior on 93 oct, 100 oct, and 116 oct.
I have the patch on my rom to completely disable the knock sensor but i do not want to run the engine with KC off for any extended period of time for obvious reasons.
my question is would it be possible to get a patch where i can disable knock control below a certain rpm/load. I know almost everyone with a built motor would love this. I really dont wanna have to buy an AEM just for knock control, especially when speed density on the stock ecu is so close.
/rant
at low load/ vacuum if i rapidly press the accelerator i will get a knock spike of up to 18-20 sometimes, sometimes it wont knock (usually 50/50). the engine will also knock right around 3500 rpm no mater if im at 15 psi or in vacuum, at 20% TPS or 100% TPS. needless to say when this happens the timing pulled ruins the run. I saw this on the dyno and the difference between a clean run and a run with phantom knock was 430 whp vs. 380 whp. If i can get through the vacuum/boost transition and past 3500 rpm without knock the engine does no produce any knock, phantom or real.
I know this is phantom knock because it does this no matter how much timing is there, it also has the same behavior on 93 oct, 100 oct, and 116 oct.
I have the patch on my rom to completely disable the knock sensor but i do not want to run the engine with KC off for any extended period of time for obvious reasons.
my question is would it be possible to get a patch where i can disable knock control below a certain rpm/load. I know almost everyone with a built motor would love this. I really dont wanna have to buy an AEM just for knock control, especially when speed density on the stock ecu is so close.
/rant
Oct 16, 2008, 09:14 AM
#3
Are you getting SES with the phantom knock? Only reason I ask, I was getting phantom knock and in the end, my knock sensor went bad with a SES indicating so. When replacing the KS, I found my sensor was lose, I could remove it with just my finger tips. After replacing the sensor, all phantom knock went away.
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Oct 16, 2008, 10:32 AM
#9
Are you getting SES with the phantom knock? Only reason I ask, I was getting phantom knock and in the end, my knock sensor went bad with a SES indicating so. When replacing the KS, I found my sensor was lose, I could remove it with just my finger tips. After replacing the sensor, all phantom knock went away.
Oct 16, 2008, 10:36 AM
#12
Account Disabled
put it back on the dyno and put on "rabbit ears" and see if you hear knock. if you got 10+knock you should be able to hear it easily. if it is indeed just phantom knock +1 on checking if you sensor is bad.
Oct 16, 2008, 11:19 AM
#14
like i said that the phantom knock does not happen 100% of the time, some runs are knock free others arent. and putting in 116 oct had ZERO effect on the knock behavior.
i dont believe that my sensor is bad, its just that i have a fully forged motor with big cams and a noisy clutch and there are harmonics at play that are tricking the sensor into thinking that there is knock when there is not.
also the knock sensor behaves as it should at WOT, its just getting past the vacuum/boost transition and 3500 rpm load cells that is the problem.
I guess i should say that the knock count does not hold throughout the pull, it spikes then tapers off as the pull continues, but at that point the ecu is trying to play catchup and get the timing back where it should be and it just kills the power for that run.
I think that being able to set when i want my sensor to listen for knock and when not to would be ideal. I will just do my tuning of low load with det cans.
I will however still check my sensor
Oct 16, 2008, 11:28 AM
#15
Evolving Member
Mine does it also, right at 3000-3500 rpm, changing afr or timing has no effect. Its less likely to happen if im easy on the throttle, if go from like 60 load to like 100 or 120 load, it will get 6+ counts of knock. If i start at >3500 rpm it wont do it. I pulled a lot of timing all around that area, which started to effect my crusing performance. My engine is stock internals with a clutch swap. (OEM replacement). It really does ruin a run when you start at 2700 rpm and get knock at 3500 and loose 2* timing from 6 cts knock. Escecially when all i have is 11-12* at redline. Ill check my knock sensor for tightness and check other hardware to make sure nothing is vibrating/touching. It honestly cant be knock, running a 12.8-13.3 afr at 3500 rpm at 0psi at like 22* timing cant be causing knock. I had timing all the way down to 17 before i said screw it and just flashed back to normal tune. Nothing i did changed the symptoms. I can pretty much make it do it at will, ive figured out when and at what conditions cause it, but no tuning can fix it... Boo...