Engine management config
Discussion
Hi All, sorry to keep bombarding the forum with new threads, I'm in the process of understanding my new car and have now turned my attention to the engine management. I think I have this fully sussed, but I'd appreciate a confirmation and answer to one question.
The engine is mapped by engine speed and TPS, with an adaptive function which learns offsets as a function of lambda and they’re saved into the main map. There IS a MAP sensor but which only serves as a barometric reading (and to provide adjustment if the air filter is getting blocked!) as it lives in the intake manifold up stream of the throttles.
When the engine isn’t mapped by MAP, there is no way to implement a throttle bypass for idle control, which is why there isn’t one…
Is this about correct?
There IS however at least one vac takeoff on one throttle, presumably for the brake servo, which leads me down an interesting route with regards the propensity of the pivots to start leaking in that your brakes will get worse if it happens on that throttle!
But why isn’t there a vac compensation on the fuel pressure regulator on my Cerb? I’ve seen that it is plumbed in on the Tuscan, though possibly not to engine vacuum (which it should be). Mapping by TPS without this could easily put the engine management into a “chase my tail” adaptive loop, and also reduces the precision available to the injectors at light throttle…
Comments?
The engine is mapped by engine speed and TPS, with an adaptive function which learns offsets as a function of lambda and they’re saved into the main map. There IS a MAP sensor but which only serves as a barometric reading (and to provide adjustment if the air filter is getting blocked!) as it lives in the intake manifold up stream of the throttles.
When the engine isn’t mapped by MAP, there is no way to implement a throttle bypass for idle control, which is why there isn’t one…
Is this about correct?
There IS however at least one vac takeoff on one throttle, presumably for the brake servo, which leads me down an interesting route with regards the propensity of the pivots to start leaking in that your brakes will get worse if it happens on that throttle!
But why isn’t there a vac compensation on the fuel pressure regulator on my Cerb? I’ve seen that it is plumbed in on the Tuscan, though possibly not to engine vacuum (which it should be). Mapping by TPS without this could easily put the engine management into a “chase my tail” adaptive loop, and also reduces the precision available to the injectors at light throttle…
Comments?
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