My knock level reading on the PFC Commander is creeping up every so often and im not too comfortable with it...
What causes the knock level to rise? waht can i do about it.
A small mic picks up the knock level. What sort of levels are you seeing, I get about 40-50 or so at most. Although some people see higher like around 80.
Is that the norm then??? I thought that they should be around the 20-30 mark???.....
What causes it, to go up?
20-30 pah thats nothing, the knock warning light doesnt come one until 60, so you are quite safe
It depends on the engine, if it\'s ported it can give you a higher reading.
it also depends when you are getting this reading. It may be occuring as you back off the throttle which is fine.
Set your Power FC to monitor 1 channel (knock) so that you can see it clearly and keep your eye on the knock level as you accelerate. I sometimes get high readings like over 130 but it\'s never on throttle/boost.
Phew! Last week i saw a max reading of 111 and was very worried. But if someone here is chilled about seeing 130, then i\'m not going to worry too much! Besides, she\'s still ok now, and as far as i understand it - if you get proper detonation, you can wave goodbye to an apex seal or two.
Nar engine is not ported single turbo though. I\'m not seeing anything as high as 60 but at least i know that i\'m not at risk.... IS the PFC an accurate reading.....
Quote from: dreit also depends when you are getting this reading. It may be occuring as you back off the throttle which is fine.
Set your Power FC to monitor 1 channel (knock) so that you can see it clearly and keep your eye on the knock level as you accelerate. I sometimes get high readings like over 130 but it\'s never on throttle/boost.
I get the same reading as you come off throattle. When Max at Reworx was mappin mine, he had to switch the knock sensor off as it kept on buggin. I think it was causing due to faulty sensor or something..
well all the PFC is doing is reading the voltage from the Knock Microphone sensor. So the PFC is accurate, all depends on the sensor itself.
The mic can pick up general noise, i usually get readings of 15-20, i had a conversation with pip about my readings when i got a couple that went over 130 under wot and he said it was nothing to worry about...
this is good to know as i was getting worried that mine were high.... but it would appear not :Thumbs-up
So at what point do you have to worry then?
if you are that worried about Knock levels, buy a J&S knock sensor.
If the car is mapped and the AFR\'s are fine then all should be good. It\'s probably better for you to buy an AFR gauge, then you\'d know if you were running lean that you\'ve got a problem.
Scoobytek do a good one (LM-1) i think for £290.
the occasional high knock reading is fine, probably just noise. if you are getting constantly high readings then its time to get the map checked.
i\'m running a std engine (not ported) HKS intake, hard intercooler pipes, aftermarket down pipe, dragon mid pipe & blitz silencer. i know i\'m on the limit without going down the mapping route (to be done soon as i\'m running just below std boost settings). my highest knock reading (on the PFC) is 30-50 when cruising about 70-80mph. i have been using tesco 99 ron and or optimax to be extra safe.
Or the knock sensor changed! About half the cars I map have faulty knock sensors.
Quote from: Donatothe occasional high knock reading is fine, probably just noise. if you are getting constantly high readings then its time to get the map checked.
My knock on the PFC reads 130 just on idle ;) get about 160 average IIRC.... I put it down to the Knock sensor being knackered because if them levels were duff it wouldnt have got me 1 mile down the road.
I\'ve seen 180+, I\'m sure I\'ve seen 200+ but I\'m nor sure what the sensors range is so that may not actually be possible :)
180+ was at the Nurburging - lifting off on the last straight, theres a video of the fireball some where :D
My knock sensor goes crazy some times, flashing for ages while cruises dont really see the point in changing it tbh. I know the car\'s map is fine and its done 12000-15000 miles like it, including a lot of dyno time, nos tuning and nurburgring trips :)
Quote from: 20B_boyI\'ve seen 180+, I\'m sure I\'ve seen 200+ but I\'m nor sure what the sensors range is so that may not actually be possible :)
180+ was at the Nurburging - lifting off on the last straight, theres a video of the fireball some where :D
My knock sensor goes crazy some times, flashing for ages while cruises dont really see the point in changing it tbh. I know the car\'s map is fine and its done 12000-15000 miles like it, including a lot of dyno time, nos tuning and nurburgring trips :)
LOL, we\'ve seen 199 when letting off with the Stealth\'s new engine, I think 199 may be the highest it can go. Is very stange because we got knock on the old engine around the 90 mark all the time, so we changed the sensor during rebuild and now we get knock between 20-40, but when engine is cold we still get random knocks of 160+ when just cruising or light throttle with the heat warning light flashing like mad. Then at Anglesey doing over 150miles of track driving the heat light didn\'t flash once :rolleyes: So think i\'m going to ignore it from now on and set it to only warn at anything over 150, the fueling is spot on so no worries :cheers
Paul:)
It makes me parranoid, but I get random spikes of 130 ish all the time, usually off throttle. I turned the flashing light off as it was annoying me. (very sensitive to flashing red lights !!)
i have a street ported engine running a T04R single turbo and see knock of about 2-4 on cruise on the motorway in 5th at about 70mph. the other day at 1bar boost about 7k rpm i only saw knock of about 4-6 although some days it reaches just over 30 if im on and off the throttle alot through gears etc.
Alot of the high knock on deceleration and cruising is to do with how lean the car is running. It will normally be just a few cells that this occurs in richen up fuel in that cell and knock will go right down.
Every fd is different, some can cruis at 14.7:1 no problem others run a bit rough at the afr, some give high knock at that afr some don\'t.
Just add my findings.
Generally during a blast when I let off the gas I can get 110 but not always. This only happened after the rebuild and porting so maybe it is the porting or maybe another duff sensor.
The guys at RE:Worx who did an excellant rebuild do not see it as a problem and thats fine with me.
Keith :WaveBye
how are you actually getting readings in numbers i just see the bar going up/down or should i say left/right
Press the \'up\' arrow on the moniter screen and you\'ll get peak readings to the right of the live figures.
have seen a reading off 20 with the knock sensor unplugged. go figure oh and the wiring is fine
Got my highest knock reading of 123 on the way home from work today.. but the knock warning light on dash (which is the heat warning light i believe) didn\'t even blink..
So i\'m hoping everything is ok lol...
Quote from: Icesurf3rGot my highest knock reading of 123 on the way home from work today.. but the knock warning light on dash (which is the heat warning light i believe) didn\'t even blink..
So i\'m hoping everything is ok lol...
Have you turned off the warning flash in Etc -> settings or whatever?
I saw constant (on/off throttle, values dropping while accelerating) 30-40 and peak of 70 on a base map with just a cat-back, my thinking is faulty knock sensor or a \'noisy\' engine, will get it back in with an egt and afr gauge to see exactly what\'s going on so I can decide whether it\'s worth keeping the PFC in for the extra info available while I save up for decat, upgraded intercooler etc :)
PS if it\'s just noise being picked up by the mic and the std ECU retards ignition based on knock levels how much is the power output being reduced by?
Cheers,
Alex
Phew..i just experienced my first high knock of 80...and I thought that was high!......drove it last night and took it up to 180kph top speed, that was fun, lucky there wernt any pigz around.