Any One used Carchip Data Logger?
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Any One used Carchip Data Logger?
A friend of mine attached his carchip datalogger to my car. I wanted to trouble shoot problems under-boost. When the unit was attached we drove the car for about 2-3 miles. We boosted frequently to get some results into the datalogger.
Just as a heads up, I experience frequent bucking or slight hesitation under boost.. It could be either Fuel or ignition. BTW, I just changed my plugs and they are gapped accordingly.
We then viewed the data and notice some variables which I needed some explanation on. There is a a section called "Fuel Trim Status".
The following variables that I have are:
*Short-Term Fuel Trim (Bank1) - 3.13%
*Short-Term Fuel Trim (Bank2) - 1.56%
*Long-Term Fuel Trim (Bank1) - 9.38%
*Long-Term Fuel Trim (Bank2) - 9.38%
Need some explaining on this one, for those of you who are knowledgeable on this.
Also the data-logger also recorded a speed-sensor problem.. Not sure if this will cause performance issues, but its a possibility. Sorry for the long post.. Thanks.
Just as a heads up, I experience frequent bucking or slight hesitation under boost.. It could be either Fuel or ignition. BTW, I just changed my plugs and they are gapped accordingly.
We then viewed the data and notice some variables which I needed some explanation on. There is a a section called "Fuel Trim Status".
The following variables that I have are:
*Short-Term Fuel Trim (Bank1) - 3.13%
*Short-Term Fuel Trim (Bank2) - 1.56%
*Long-Term Fuel Trim (Bank1) - 9.38%
*Long-Term Fuel Trim (Bank2) - 9.38%
Need some explaining on this one, for those of you who are knowledgeable on this.
Also the data-logger also recorded a speed-sensor problem.. Not sure if this will cause performance issues, but its a possibility. Sorry for the long post.. Thanks.
Short term fuel trim is the % amount of fuel injector duty cycle increase/decrease needed to target stoichometric(14.7:1) air/fuel ratio based on front 02-sensor feedback during closed loop, light throttle/load driving, for changes in air density due to temperature, pressure, and humidity.
Long term fuel trim is the same type of correction except it's more dependent on long term variations such as MAF aging, altitude, fuel system abilities, etc., and is stored in the ECU for future trips/calculations to make the short-term fuel trim range smaller.
The problem with monitoring these variables and trying to gather insight into how the air/fuel ratio is changing is that first it is only valid data during closed-loop operation, ie light throttle/load, and second OEM 02-sensors are narrow-band therefore they can't determine between 14:1, 13:1, 12:1, etc, it just tells the ECU whether you are on the rich or lean side of the 14.7:1. The farther you get away from the 14.7:1 "mid point", the less accurate they are.
You can't gain much from monitoring narrow-band 02 sensor data, other then if you are rich or lean by the ECU adding or subracting fuel.
Long term fuel trim is the same type of correction except it's more dependent on long term variations such as MAF aging, altitude, fuel system abilities, etc., and is stored in the ECU for future trips/calculations to make the short-term fuel trim range smaller.
The problem with monitoring these variables and trying to gather insight into how the air/fuel ratio is changing is that first it is only valid data during closed-loop operation, ie light throttle/load, and second OEM 02-sensors are narrow-band therefore they can't determine between 14:1, 13:1, 12:1, etc, it just tells the ECU whether you are on the rich or lean side of the 14.7:1. The farther you get away from the 14.7:1 "mid point", the less accurate they are.
You can't gain much from monitoring narrow-band 02 sensor data, other then if you are rich or lean by the ECU adding or subracting fuel.
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MaximaDrvr
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Aug 19, 2015 08:20 PM