Bored, can't work on the setup, but wondering if anyone has seen something like this, and has any ideas? ("Misfire" probably a bit misleading, sorry)
Between 35-45MPH, the engine starts bucking like there is no tomorrow. Definitely feels like fueling issue. This is under heavy throttle, normal operating temp. Light acceleration the problem isn't quite as bad, but there is definitely a sag in this range even at light throttle. I have seen no evidence when disabling PE that the motor is running lean here if I am gentle on acceleration.
I've extensively worked on getting BLM's close to 128 under "normal" conditions, however without a wideband I'm a bit handicapped on this problem since it's under heavy throttle when it should be going rich/open loop.
I've messed with AE fairly extensively, and PE a bit. What I can't figure out is why there is an issue in the same MPH range....I can be in 3rd or 4th gear (2368/1393RPM's respectively) and the problem still happens between those MPH's. Since everything is based on load and RPM, there is no reason I can figure as to how or why it could be MPH related. Over or under that speed range, it doesn't exhibit the same behavior. At 65MPH in 4th I'm turning right around 2200RPM, which is the same RPM range as 35-45 in 3rd and I have no problem with it breaking up at 65MPH, so again it doesn't seem to be RPM related.
The pickup coil and module are both new within the year (cheap parts store pieces, but had to use what I could get) but I keep going back to the MPH correlation, which doesn't point to ignition. The speedometer is driven off the DRAC/VSS, and I don't see any problems with speed display. The datalogs don't show any error in speed reporting.
No datalogs so far, since the '165 is so poor at keeping the stream going I normally make changes by feel when it comes to AE/PE. '7727 is coming, I swear. After I rewire my daughters Power Wheels. :)
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