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Re: disconnect battery... Trionic ECM Posted by Peter [Email] ![]() ![]() ![]() In Reply to: Re: options - TECH2 or OBD2 reader, or disconnect battery.., Rob D, Fri, 24 Dec 2004 08:00:30 Members do not see ads below this line. - Help Keep This Site Online - Signup |
900SET (turbos) have "Trionic" ECMs (engine control modules) and DI casettes (direct ignition). This means no conventional knock sensor, each cylinder monitored individually, maximum turbo boost and ignition timing adjusted according to octane fuel used, temperature, etc, etc...
When you disconnect the battery, you have to re-enter radio security code, station presets, and engine failure codes are lost (that is why the check-engine-light goes out).
You ALSO lose the engine control settings, and the Trionic ECM has to "adapt" all over again. Besides emissions, some claim that you need a sustained condition of high boost on the highway, for 3-5 seconds in a high gear (3-5th), with engine fully warmed up, before the max boost is set properly, and the ECM 'adapts' completely after loss of power. Boost gage has to be between yellow and red for this to happen, and for several seconds. After that, the ECM adapts continually, not just once after battery power is restored.
I have never found anyone who could confirm this with any real authority (Q. for Anders?), but it does make some sense, because the ECM has to adapt to both high and low octane fuel.
It is also claimed that if you operate a 900NG turbo with a failing thermostat (engine temp never above 1/3 travel on the gage), the ECM will not adapt properly, and mpg and power will suffer much more than with just a cold engine.
posted by 68.248.201...
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