What happens if I unplug cycling valve on a stock setup?
#16
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Well.... I still like the theory, but I would kick myself if I broke something trying to keep my son from breaking something. I appreciated everyone continuing to chime in on this.
#17
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Interesting - I will do some testing to see if I can reproduce that (timing reduction if boost pressure is too low). I have not seen the timing reduction happen, but I suppose it is worth taking a more in-depth look at... I am still quite doubtful, as the the turbo responds different depending on gear / road / altitude / ect, so I'm not sure how the KLR would determine that there is not enough boost.
Again, I am not saying that unplugging the CV absolutely will generate this fault, as I have seen various problems go undetected by the KLR, but it is supposedly designed to catch this specific issue.
It won't break anything.
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Originally Posted by Oddjob,
It won't break anything.
#19
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#20
Burning Brakes
I sort of answered the question last night...I bought two extra KLR's because I thought mine was the cause of my low boost (and I was wrong.) the first KLR had a chip in it already, but I still swapped in my Autothority chip into it. No change in running. Last night, I installed a never opened, virgin KLR, and the car no longer goes into low boost mode...it holds all .5 bar it can currently muster.
Is this something you've found before? Whatever issue I have with boost is on the exhaust side, and I'm tearing it apart next month.
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I don't have the manual in front of me here at work, but there is verbage that says something about the boost level has to be 0.45 bar below the design setting for the KLR to potentially detect a fault, and that there can be low boost problems that do not trigger the diagnostic fault code. Likely the KLR is using its internal manifold pressure sensor and comparing the measured value to a set limit based on rpm and throttle position, could also be an average/time function similar to the DME overboost protection.
Again, I am not saying that unplugging the CV absolutely will generate this fault, as I have seen various problems go undetected by the KLR, but it is supposedly designed to catch this specific issue.
It won't break anything.
Again, I am not saying that unplugging the CV absolutely will generate this fault, as I have seen various problems go undetected by the KLR, but it is supposedly designed to catch this specific issue.
It won't break anything.
https://rennlist.com/forums/944-turb...e-and-klr.html
Last edited by Rogue_Ant; 05-08-2012 at 08:10 AM.
#22
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I was cleaning up old threads that I am subscribed to. I notice I never returned with my result. I have run the car without the cycling valve plugged in and the max boost is 1.2 bar. No ill effects that I can tell. However, I also learned the collectors insurance doesn't require that I have a seperate car for my 16 year old driver as long as he is a full time student. Unfortunately for him, he cannot drive the car with the current insurance.
So, I can disable the boost easily but no longer have a reason to.
So, I can disable the boost easily but no longer have a reason to.
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I recently used the blink code to find a bad knock sensor. When sensor was checked at klr plug pins 11&13 to verify blink code sensor was open. Replaced with a good used one, blink code went away.
Any dianostic fault that the KLR identifies and displays a blink code, will trigger the limp mode. I have found this to be true (KLR will operate in limp mode if the KLR is giving a blink code fault) and factory documentation supports that. If in doubt - unplug the TPS, read the blink code, and see how much boost a stock car will make.
Page 28-30 of the Turbo supplement:
"The knock/charging pressure system includes a self-monitoring system, which can output a recognized defect w/ the help of a test adapter...output is in the form of a blink code. If a defect has been found, the engine will operate on a safety system (basic charging pressure up to approx 0.3 bar overpressure and 6 deg later ignition)..."
Code 3-1 indicates boost pressure too low. And possible causes listed the DME/KLR Test Plan include "plug has fallen off of timing valve... Wire break... Break in pressure hose to KLR control unit." etc.
No guarantee that the KLR will actually identify low boost as a fault (its not a very robust/reliable diagnostic system, e.g. I have never seen the KLR identify excessive boost, nor knock sensor failure even if its unplugged). But according to documentation, a low boost fault check does exist in the system parameters, and if detected, it is supposed to generate the blink code and trigger the limp mode.
Page 28-30 of the Turbo supplement:
"The knock/charging pressure system includes a self-monitoring system, which can output a recognized defect w/ the help of a test adapter...output is in the form of a blink code. If a defect has been found, the engine will operate on a safety system (basic charging pressure up to approx 0.3 bar overpressure and 6 deg later ignition)..."
Code 3-1 indicates boost pressure too low. And possible causes listed the DME/KLR Test Plan include "plug has fallen off of timing valve... Wire break... Break in pressure hose to KLR control unit." etc.
No guarantee that the KLR will actually identify low boost as a fault (its not a very robust/reliable diagnostic system, e.g. I have never seen the KLR identify excessive boost, nor knock sensor failure even if its unplugged). But according to documentation, a low boost fault check does exist in the system parameters, and if detected, it is supposed to generate the blink code and trigger the limp mode.
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Lart more than likely had the signal line to the CV rupture. In that case, no pressure gets passed to open spring on wastegate. So he could have spiked to well over 20lb boost, ran extremely lean and blown a few gaskets. DME had no idea of the manifold pressure and timing and fuel was set for .8 bar.
#25
I run a manual boost controller and a dual ported waste gate to control boost. I did leave the CV installed - it is connected electrically but not connected to any vacuum/boost. I left the device on the engine and electrically connected because I understood that the CV played a part in the the knock detection system. Am I wrong about this? Will knock detection still work if the CV is electrically disconnected? I realize that the knock detector is a separate device but are the two devices (CV and knock det) linked systematically so that both must be present to work?
#27
I run a manual boost controller and a dual ported waste gate to control boost. I did leave the CV installed - it is connected electrically but not connected to any vacuum/boost. I left the device on the engine and electrically connected because I understood that the CV played a part in the the knock detection system. Am I wrong about this? Will knock detection still work if the CV is electrically disconnected? I realize that the knock detector is a separate device but are the two devices (CV and knock det) linked systematically so that both must be present to work?
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