by Murray Betts » Thu Dec 04, 2003 23:40
This shows the injector pulsewidth measured after a cold start from about 10degC, unassisted (foot off throttle).
You can see the afterstart enrichment lasts for about 10sec, the engine then runs on the basic map fuelling corresponding to the temperatures for another 10sec or so, and then the warm up begins to take effect.
I have not yet measured the pulsewidths at other temperatures, so I cannot at this stage say how much afterstart fuelling you get when colder, for example, nor whether it ramps off at different rates.
If you are experiencing afterstart stalling/stumbling, you may be able to relate it to a certain fuelling phase from this plot.
I'm not sure exactly what happened at the 105-110sec range where the P/W does a couple of dips; it could be the feedback starting and coming under closed loop control, it's the right sort of timescale and the P/W seems pretty constant after that time.