View Full Version : Knock or Not?
knights19
06-13-2018, 12:59 PM
Hoping someone here can start me off on my learning curve of Chrome and tuning.
It's my first time running the VR4 motor after 4 years of building a car with the motor in the back.
First run gave repeated engine cut at various throttle positions which I thought from the log was due to knock count (which I can't hear in the car) but I can't pinpont what is causing it. At first I thought it was boost pressure but that doesn't seem to correspond to the knock values. Timing is being cut causing the driveability issue (to say the least), but to me the knock voltage doesn't seem right. Help appreciated...9651
anyonebutme
06-13-2018, 02:44 PM
You have bigger issues than that I think. You have 0 knock volts but a base of 6-8. You have 5 degrees of commanded timing at idle tps.
anyonebutme
06-13-2018, 02:46 PM
Also your idle tps seems high to me, sure your idle flag is being set?
knights19
06-14-2018, 03:05 AM
You have bigger issues than that I think. You have 0 knock volts but a base of 6-8. You have 5 degrees of commanded timing at idle tps.
Capture was at around 3000rpm 50% throttle just before the knock registered (couldn't load the csv file), timing was cut to 5 by the ECU and I backed off but maybe not to idle position but I will check the idle reading. 10-13% is idle yes?
Guess I need to check the 5v supply to the sensor.
Idle switch is working okay.
I do have a knockVar of a fixed 255 which I guess would also point to an incorrect sensor reading, biggest pointer being the voltage from the sensor?
Was a new sensor when I rebuilt the engine, but could be duff. Is there a way to plug in a spare sensor and mount it somewhere so that it still reads knock without having to remove the intake manifold?
knights19
06-16-2018, 09:02 AM
Further investigation shows I am getting fueling issues mainly because of my intake piping length causing lag and the maf position not being able to read the air flow. Is there away to use MAP instead of airflow. I did read in one of the threads about it being added to Chrome.
knights19
06-18-2018, 02:22 AM
Anyone?
anyonebutme
06-18-2018, 09:53 PM
You can unplug the MAF and tune using the alpha N table (I think that info is in the chrome thread), but I don't recommend it. As long as there is no leaks the distance of the pre turbo tubes will only effect the "accel" tuning section. Can you post more details on the car and the setup?
knights19
06-19-2018, 03:49 AM
Not seen any info on the N Table.
Problem is I have long pre and post turbo pipe lengths which is causing the issue.
There is a motorsport place an hour away that do a piggyback ECU for the GT to use additional MAP and temp sensors but will cost me as much as the Chrome.
9657
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