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21

Ok, before I will answer your specific questions, let's do some introduction on bus systems. It could be that you know parts of these things, but I will start here as people with little or no IT or electronics knowledge should be able to understand this as well. Bus Systems In electronic systems signals are sent from one chip to another using wires (let's ...


7

OBD II is a US government mandated diagnostic interface. This interface is guaranteed to provide a specific set of information including but not limited to engine computer data and engine computer trouble codes. When OBD II was rolled out the US government did not force the manufacturers to also standardize the communication interface to the engine ...


1

It is not actually. The OBD2 sensors probe the throttle positions in terms of percentage, not the actual mechanical position. The idle of the vehicle Volkswagen polo was governed by ECM, and the rpm varies from 550 -900rpm and most standard is 600-800. It was based on the various factors as below. Ambient temperature Engine temperature Fuel Quality ...


2

I don't know specifically about your car but in general it is possible. Some cars have a cam that opens the throttle plate when the engine is cold to increase the idle. My 99 Nissan Almera has such a cam. The cooling system has two purposes. The obvious one is to disperse excess heat and prevent the engine from overheating. The less obvious one is to ...


6

The ELM327 is (almost?) as powerful as any other diagnostics solution. That's simply because it only translates the low level OBD protocols to some other format. Bluetooth connections on mobile phones seem to be flaky on many devices. Usually, this shows as established connections suddenly failing during transfer. Restarting the app, and/or turning the ...


4

Bluetooth ELM327 adapters are horrible, I found the Bluetooth connection to be extremely unreliable. Spend some extra and get the USB version, if ELM327 is what you want. The Android apps have the potential to show the same information as the PC applications, but usually the features on the Android apps are limited, it depends on the applications themselves. ...


6

Your question need answered with another question. What diagnostic capability do you want? While the generic side of OBD-II leaves something to be desired and has been stagnant since it's inception, the manufacturer specific side of OBD has made tremendous leaps and bounds from where it started in 1996. My old 1996 Nissan Sentra had about 2 dozen pids. ...


6

Did you set the protocol for the chip to monitor on? e.g. ATSP5 for KWP-2000 or ATSP0 for "best guess". What about checking the headers as well - ATH1? I use the following string of commands to monitor my full KWP bus, which is obviously different from CAN, but is similar enough that it might be of use: ATI -- check connection from app to scan tool ATH1 ...


5

The basics are quite simple. The motor generates a certain torque N and a certain power P at a given RPM. Further more, the relation between power and torque is: P = C * N * RPM where C is a constant to convert all that odd units. For N, P in SI units, it is C = pi / 30 Neglecting any losses, Power is conserved from the motor to the wheels so you ...


5

Some motorcycles have a CAN BUS, some don't The OBDII connector type is simply a standard instituted by the SAE (Society of Automotive Engineers). In 1996 the US government mandated that all cars sold in the United States conform to the SAE OBDII standards. They didn't specify motorcycles. As result, a myriad of on-board diagnostic methods were ...


2

Most motorcycles do not used OBD II protocol especially Japanese ones. Harley use something that is the closest to OBD II , I am not sure they might even be exactly OBD II. First of all we must know what is OBD II, its a set of plugs and adapters, protocol which allows connectivity to a vehicle's computer. Though there is no exact answer as to why ...


1

To my knowledge, the OBD-II standard does not require manufacturers to provide this information. That said, some manufacturers may make steering angle information accessible through make-specific cables. This is usually done to give dealerships the ability to calibrate or recognize a replacement sensor. Even if this information was available, you would ...


6

When you say OBD i'm assuming you mean generic data. The answer is outright NO. OBD generic data has no parameters that the alignment can be gleamed from. If the car has a steering wheel angle sensor then maybe you could tell if something is wrong. This data would be available in manufacturer specific. If the angle has been off for a long time at high ...


2

Yes, provided the following conditions are met: the units for the values MAF and fuel flow values are consistent. if you're using OBD-II parameters the values are usually in different units. In fact, fuel flow is usually volumetric (L/hr) and not mass flow like the reading from the MAF so you would have to correct for that by injector flow rate, I'm ...


2

From the Wikipedia page on OBD-II PIDs. PID 1E designates if the Power Transfer Output (PTO) is active or not. PID 65 is the sister PID to 1E designating if 1E means anything, supported or not. A PTO is a device that attaches to an engine/transmission that does other work besides driving the vehicle forward. For example a dump truck commonly had a ...


4

You can do this through the OBD-II protocol (SAE J1979).: +------+-----+-------------------+ | Mode | PID | Description | +------+-----+-------------------+ | 01 | 5E | Engine fuel rate | ( liters/hour ) +------+-----+-------------------+ | 01 | 43 | Engine RPM | +------+-----+-------------------+ You can use the RPM to figure out how ...


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If you know what the fuel pressure is at the injector, what size of injector you have (flow rate), and you pull out the pulse width (how long the injector stays on), you can figure out how much fuel is being injected each and every time it fires. You should be able to pull out the pulse width at any given time from the ECU, if you pull the right PID. It's ...


1

Some ideas... You could also use the fact that typically if your vehicle speed is/was accelerating, and the RPM drops sharply without the vehicle speed dropping, then the driver shifted up. If the RPM increases quickly and the vehicle is not accelerating, then the driver down shifted. This would not account for dropping it in neutral. You might be able ...


4

What you want to do is not easy and is an exercise in data analysis. First you need to know the gear ratios of the car and the tire size. The tire size will allow you to calculate the RPM of the output shaft. This is where the fun data analysis comes in. The gear ratio will converge as the clutch engages. For example if your sitting at a stop the gear ...



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