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Altezza basemap... VVTI PID 20% minimum DC?


Davidv

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Hey guys,

For ages I've just assumed that my cam angle offset has been incorrect as it always shows 12 deg advance even if I set it to zero.

But what happens is that when the engine gets to the rpm / ECT range where VVTI can be turned on, it has 20% minimum pulsewdth which pushes the cam to 12 degrees advance.

So I've been thinking about changing to a custom PID so I can reduce this down until it shows closer to zero.

But just wondering if there's a good reason why it's set to 20%?

Is it bad to have the cam resting on its "base" position.

Take a look where the yellow line is on the graph, and then just to the right of it where the minimum DC drops to 5.

xq0efd3a.gh0.jpg

 

 

Edited by Davidv
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Hi David,

Have you done the cam angle test yet? If I were you I would start there and see what the results are. It is not bad to have no cam timing and to be in the resting position. Try this and let me know the results.

 

Cam angle test.PNG

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Disregard this!

Found it's a physical fault with the pulley... It had been rattly so I replaced it... It must have been jamming at 12 degrees advance under some conditions.

Now it's running like a dream and follows the target perfectly.

Thanks

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