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T77911S T77911S is offline
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Join Date: Oct 2006
Location: MYR S.C.
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Quote:
Originally Posted by psalt View Post
The biggest misunderstanding about the CIS lambda system is that the way they made the mixture trim system work was to make the K Basic parameters all way too lean and use the FV to drive the mixture toward rich. This is why you need the ECU and FV to get anywhere near the correct fuel curve, even with a disabled O2 sensor. This is somewhat counterintuitive, the "default" mode should be too rich, it is if only the O2 sensor fails, but if the ECU fails, the engine still runs, but much too lean.

maybe i have been under this same misunderstanding. i always thought the open loop mode was rich, to provide richer mixtures in the upper RPM's and the O2 sensor was there to bring the mixture back to a leaner condition for emmissions, drivability and gas mileage. if it works backwords from this, the way you say, how does it not go too lean at WOT?

i think what MCA was saying is that if he changes the idle mixture from say 14.7 to 14.2, that the mixture across the whole RPM range and WOT should go richer by .5 points.
i had done a test of this with an LM@ in the past, but i had a fuel line issue back then, but i think the mixture did follow this, dont hold me to it though. so craig, there is another test you can do when you get the LM2. when i get it i will do this again too.
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Old 01-06-2011, 08:12 AM
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