July/August 2020

JULY/AUGUST 2020 AFTERMARKET 23 EYEBROW www.aftermarketonline.net opean Ignition & Eur Engine Management - A • Best Coverages ll Makes - All Models • 1 00+ • Over 25 SKUs • Intelligent C Lambda Sens Engine Management Sensors s • Ignition Co e xhaust Gas T E est 00% es onso or • ils e Senso mperatur rs YOUR FIRST CHOICE .ww U.S. Corporate Office: +001-636-257-2400 • Customer S Office: 0121 459 8006 TON BUSINESS 7 CASTLE ROAD • KINGS NOR ALKER PRODU W ww d @ lk RE • BIRMINGHAM, B30 3HZ TIONS EUROPE OPERA N QUALITY oducts.com I p r ech alker T o ucts.com ope wa erpr ervice • sales CENT eur CTS • : +001-636-257-1700 • • WEST MIDLANDS, UK PRODUCTS nical Support: +001-844-252-0114 intrusive real time response to cylinder contribution, that sounds like a lot of words describing combustion to me. Let’s consider the simple logic here. A rotating engine has a given mass energy, the more cylinders there are, the smoother the engine. That’s part of today’s challenges. With smooth running adaption, cylinder select and active engine damping, not forgetting noise cancelling technology, identifying a problem is not so easy anymore. The mass energy is a combination of the rotation and reciprocating components. These are, by nature, always in conflict. They do, however, form a repetitive vibration pattern. This will vary for each engine design number of cylinders and operating condition. This pattern is determined by disturbance or orders. A single crankshaft rotation is the first order. Each cylinder combustion event is contributing to what is considered combustion orders or how many events occur per crank rotation. So, a half order will occur every 180 degrees, and a second order every 720 degrees. Therefore, if each combustion event releases the same energy or mass to the piston crown, we can monitor it in real time with an 3D accelerometer mounted on the driver’s seat frame. Yes, it is really that easy! The engine configuration and number of cylinders is input together with serial engine RPM into the software wizard. The output is measured by frequency and mass in milli gravity.Any deviation in combustion contribution will be displayed as a change in mass value. So, there are our diagnostic options, success today is often achieved by several diagnostic methods. The real skill is choice and interpretation of the evidence that is the difficult bit. I have chosen simple images to demonstrate the principles. Keep well, and see you in the next issue. Fig.2 shows a single cylinder combustion failure with a significant transfer of mass to the crankshaft E1 with E0.5 and E1.5 increase in mass transfer due to rotation instability Fig. 3 shows the fuel response to a snap throttle test. For illustration purposes red represents throttle pot, green map sensor. Note there should be no response deviation from either component. blue represents a zirconia sensor response ’rich’ 0.8v within 200 ms of load request