In a previous post, I mentioned I was taking a break from spark advance tuning and 10s of thousands of fake knock counts. Now have knock retard turned off and am running stock L31 timing tables which are more conservative than what I had before. I'm now working on getting all fuel trim related items right before I go back to tackling spark and knock. Remaining issues are below. Any help or advice on any of these would be much appreciated!
1. Cold start issues. Actually starts fine, minimal cranking. But after a couple of seconds of normal operation I get a swinging idle and it will almost stall. WBO2 pegs lean when it wants to die, then swings rich when it recovers. I haven't verified, but I think stall saver is kicking in? I can resolve this a little by raising the idle with my foot, but until it warms up it will go through these cycles. In drive is worse and reverse is by far the worst. All these problems are resolved when it goes into closed loop EXCEPT reverse. Even fully warm, reverse with zero TPS it will want to die.
2. Hesitation at slow takeoff from stop. If I punch it from stop, no issues. But a slow gradual take-off will produce a noticeable (even to passengers) hesitation. I'm guessing this is due to a problem in transition from idle VE table to off idle table, but I'm struggling with how to resolve it.
3. Rich Deceleration. Most of the time taking my foot off the gas completely results in AFRs on the WB in the 11s or even high 10s. This continues all the way to almost full stop, but at 5 mph and slower AFR is going back up to 13s and 14s. At full stop it idles nicely in the 14s usually. As far as DFCO is concerned it's either never coming on or it's very seldom. I will play with DFCO but it seems like I should be resolving the rich decel first, without DFCO.
4. And now a general question for a NOOB to WBO2 tuning. I have the spreadsheet that works with the '7427 (Dave W) and I understand the general principal of making adjustments to get AFRs around stoich across the board. But the part I don't understand - we're making the changes to the VE table and we're using CL to tune. Won't the computer be making adjustments all the time based on the NB and theoretically the WB would just be seeing the the already corrected values? It doesn't seem like it would be capturing much to adjust? Would using OL to WBO2 tune work? It seems like you'd zero in on the corrections needed to the VE tables much more quickly that way.
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