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Originally Posted by Reanimotion View Post
Thanks Alan,
This isn't the injector hammering we saw in the early testing before we added the fuel damper, this is a slow and steady once per second surge or cycle.

Our injector is running at 100 cycles a second and the pressure /duty feedback loop is on 1000 cycles per second so I'm comfortable it's not injector pulse related

from appearances it's a nice cyclic curve in control pressure with a 3 or 4 pound swing +/- our target. we might be able to tune the control/feedback loop to hit harder and arrest the wobble or attack it in another way by not trying to correct a deviation that lasts less than a second.
Or adding the factory damper in the control line could be an option if it's not there now.

Hang on, Flightlead404 - is the factory damper in the circuit on your car? I had one on mine that had to be removed as it was shuttling a pulse between the original system damper and the eWUR integral unit

Primary question out there now is - is AFR being affected?
IF AFR and idle/running is good then a wobble visible at the WUR may not be affecting the fuel delivery at all
If we lock the duty cycle to an assumed pressure as Eddie suggested and UTCIS did on their unit we lose the damping effect of the PID control and probably still have the wobble in the pressure.

this mess below is from post 100 and no damper at 1/10th of a second sampling
This is the same pulsing seen with the smaller injector, only its significantly lower amplitude. Previously I saw large swings in RPM. Now, the RPM swings are there, but not enough to be that noticable on the stock RPM gauge. The MS RPM readout being much more sensitive does show it. You can hear it in the engine note.

I do not have a factory damper, I do have the damper in the eWUR block.

I don't have the data in front of me, but I believe AFR is bouncing. Since AFR is a slow to react sensor, is it possible its chasing the AFR not the target CP?
Old 02-09-2017, 06:57 AM
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