| If you look at this run you'll see it: [ http://home.comcast.net/~marshallj25/Datalog3.xls ] Click on the "RPM" tab at the bottom and look at the RPM drop between 8:32:31 and 8:32:32. It stumbled and almost stalled there, as you can confirm by looking at the "voltage" tab. If you look at the "Air Flow" tab, you'll see a chart with the airflow meter data compared to the RPM. I'm not sure what the normal range is for the Airflow meter when you let off the gas, but at a glance I don't see anything that catches my eye like a big swing or anything. So I don't think the AFM is bad in this case- if it's an air issue it's one that occurs after it's measured by the AFM. If you look at the "Throttle" tab, the signal is perfectly steady by that point since I let off the gas. I don't think that sensor's the cause either. But check out the "O2 sensors" tab- it shows the mixture spiking very rich at that point, so we know the mixture is a bit strange there, getting too rich. With that in mind, check out the "injectors" tab. We can see that the injectors are actively injecting more fuel into the engine at that point. Now I'm not sure if that's the cause of the stalling or just the result of it- maybe the ECU detects the RPM's dropping too low so it injects more fuel in an attempt to get the engine back to its desired idle point. Come to think of it, the injector utilization between 8:22:19 and 8:22:29 looks pretty low, and it remains like that until the engine almost stalls at which point it injects more fuel to get the normal idle that you see from 8:22:33 to 8:22:37. If you notice, when it's idling right it's injecting more fuel. Does our engine cut the injectors when it's coasting? Anyway, it's some more info to help you solve the problem.
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