the fuel trim looks right, ill assume 100 = untouched (100% fuel from the map). When you step down on the TPS it locks at 100 because the ECU stops looking at the narrowband during open loop. Assume when you see 100 fuel trim you are in open loop.
While the fuel trim is 97 Ill assume that 3% fuel has been removed. Basically not important. the ECU is not pulling that much and it has a max adjustment anyways to prevent a bad O2 sensor from causing serious problems.
focus on the scenario:
lets scenario. Your driving at constant throttle. The O2 sensor is flipping back and forth. You keep driving this way forever. Suddenly out of no where- the car acts up? For how long? If you just keep your foot there, does it start working again like normal?
compressor surge shows up on the maf signal- see the jagged edges?
Quote:
Here is the requested fuel trim. I'm no expert, but shouldn't that bitch be oscillating with the narrowband?
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You dont really have enough of a graph to say for sure what its "supposed to be doing" and even I have never seen a fuel trim graph from an SR20 so I am not expert either. It would make sense that it might adjust over time- but most ECU have a memory that stores up hours worth of data so a fuel trim might not move very much at ALL while you drive. In other words, it remember from the last few weeks, that in each cell, the fuel trim is a certain place to give the closest possible A/F to make the narrowband move through its center of 0.5volts, and it might only take 1-2% of fuel "trim" to cause the swing, which would be moving cell to cell since each cell has it's own fuel trim memory stored. But this is all just guess based on what I know about other factory computers.