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Discussion and questions related to the course Professional Motorsport Data Analysis
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A little background i have a ls engine with a motec m84, 10 years no issues. Engine freshen up and problems started. Randomly cuts out only re fires ones master reset, battery isolator. Could happen on the race start or lap 7 or every lap. This had a faulty alternator over charging 15.3v , replaced it and back to 13.8 to 14.1v. Changed every sensor and un picked the engine loom and checked continuity every wire good. I will put a screen shot of the data what happens only to the tps, rpm, fuel and oil pressure. I know they all run on the 5v A2 pin out so not sure if its a wiring or ecu or sensor issue hopefully you guys can give me some guidance.
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It's possible a component in the M84 has failed. Consider sending it back to MoTeC through your dealer. They should be able to take a look. Include the data file (not just a picture) in your request.
Good Luck!
The spike up to 65535 in the log channels is indicative of a reset of the hardware and the logging stopping then restarting. If you press the S key to show the individual data samples in the logging, it is likely that all of the channels had the same behaviour, they just didn't have a logging event occur when the hardware cycled. Engine Temp is an example, its normally only sampled at 1Hz, so it is likely to have missed cycle.
The alternator may have spiked much higher than the 15.3V and caused damage to the board. It may be able to be repaired, depending on what has been damaged. The age of the M84/M800 that it is based on has made component supply difficult.
I would also do a check to make sure that all of the grounds are good.
@David, a couple of birdies that visited last week said that you are hanging up the keyboard, this true?
