Cranking

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WOT until Redline, MAF looks like complete garbage. It also tops at 170g/s and used to be 220g/s in the same weather. If this entire difference were to be explained by weather factors, it would require a difference of -40 celsius and 40+ celsius... This was WOT, pedal to the metal all the time at around 150-200km/h speeds.


Car about a month ago, starts extremely rich, if at all. You can see that the MAF used to read around 4g/s at cranking around 300-400rpm, between 3 an 4 and the car would atleast start. It is overreporting, hence why the engine starts to extremely rich. Now it cranks with numbers of up to 5g/s, which is 60% more fuel?


This is the data I receive when I crank the engine and try to start the car normally. The MAF is just all over the place. I don't touch the throttle, throttle body stays steady (we took the tube off and watched it on another occasion). It should be consistent according to our logic, but you see it's not. Idle at 800rpm is normally at 5g/s, and the MAF shows the double! Logically, the car should have 3g/s at around 400rpm to start, and as you see in the graph, it's at 3g/s that the car reacts and actually wants to increase in RPM before the sensor measures 5g/s again. In the 2nd half, the engine just starts to flood and worsens the performance of combustion.

* Got Cyl 1 and Cyl 2 misfire codes occasionally, misfire is very steady.
* car runs very rough on WOT, especially between 1K and 3K RPM.
* WOT max RPM used to be 220g/s, is now 170g/s (typically meaning that the MAF is shot).
* Compression or no compression, the MAF reading should be somehow consistent, and if anything, it shouldn't be getting over 3g/s, it should be getting under 3g/s if the compression of the engine would have been shot because it wouldn't suck in any air to begin with.
* Car starts extremely rich, and just leaves a blue smoke behind me and people behind the car suffocating (floods because it reads too much air and injects too much fuel).
* MAF reading jumps between 65 and 80g/s consistently every reading (every 200ms). MAF reading during starts is complete garbage if I may say, and when it even runs on Idle, it has the same readings.

On one occasion the car started without the MAF and without 1 of its 2 leading coils connected and nothing in front of the throttle body (no filter or accordion tube). Normally it would only start with an MAF, but never without one, or barely. It would just show -40 celsius and run too rich to actually idle.

I could not find any other examples of MAF readings on cranking and idle, but if I've seen them from YouTubers like ScannerDanner, the readings seem to be very very precise and as stable as the RPM. Does anyone have an idle MAF g/s reading of their RX-8 over a period say 10 seconds? Or cranking MAF data? It would help me identify whether my MAF is shot, because these readings looks miserable and I can't believe that the PCM can make any sense of the garbage that the MAF is sending. And consider this, that this data is an average of multiple data points! It may aswell be showing 10g/s, then nothing, again 10g/s, and nothing to the PCM on a oscilloscope or a picometer.