Erratic AFRs
Jun 26, 2010, 01:00 PM
#16
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I think he meant to have you search. Over on Evo X Forums, they have some good posts about it. I can't post links here, or even the site name.
Basically what you have to do is change the latencies. Because you run almost twice the pulse width at cruise than you do at idle, the latencies affect idle twice as much. So if you add a tick of latency, idle will go richer than cruise will and vice versa. You may have to scale the injectors down when you increase latencies.
Clipse has a great post on how it all works over at that site I mentioned before.
Basically what you have to do is change the latencies. Because you run almost twice the pulse width at cruise than you do at idle, the latencies affect idle twice as much. So if you add a tick of latency, idle will go richer than cruise will and vice versa. You may have to scale the injectors down when you increase latencies.
Clipse has a great post on how it all works over at that site I mentioned before.
Jun 28, 2010, 11:30 AM
#18
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Tephra,
Did you mean to post a linky??
I've read the techniques and they're not clear on how to handle a situation where you have the trims split negative idle and positive cruise. That's why I posted the questions above. I can understand that increasing latency and then adjusting scaling can solve a problem with positive idle and negative cruise since the latency will effect the idle more. But I'm assuming changing scaling effects both idle and cruise by the same percentage.
With this assumption, to fix my - idle and + cruise, I could do the opposite; decrease latency which would decrease idle more than the cruise and then increase scaling to bring the global fueling up for both idle and cruise.
I really don't like to follow "techniques" blindly without understanding what I'm doing.
Did you mean to post a linky??
I've read the techniques and they're not clear on how to handle a situation where you have the trims split negative idle and positive cruise. That's why I posted the questions above. I can understand that increasing latency and then adjusting scaling can solve a problem with positive idle and negative cruise since the latency will effect the idle more. But I'm assuming changing scaling effects both idle and cruise by the same percentage.
With this assumption, to fix my - idle and + cruise, I could do the opposite; decrease latency which would decrease idle more than the cruise and then increase scaling to bring the global fueling up for both idle and cruise.
I really don't like to follow "techniques" blindly without understanding what I'm doing.
I need to decrease my latency value which will decrease idle more than cruise and then decrease scaling to bring the global fueling up. The iterations might look something like this:
Example: LTFT Idle = -4.01, LTFT Cruise = +11.34. The ECU is compensating to reduce the idle fueling and increase cruise fueling. If we decrease latencies we will decrease the idle trim more than the cruise. Say we decrease latency and we get Idle = +5 and Cruise +15 then we decrease scaling (adding to IPW) to increase global fueling. Then it drops trims to Idle = -3 and Cruise = +7. Then we reduce latency more and get +3 and +10, then reduce scaling and get -1 and +6. Repeat process again.
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