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Checking low side fuel pressure on a 2009 enclave 3.6. My Mac fuel pressure gauge fluctuates very rapidly at idle. But if we hold the throttle steady it gets solid at 56 psi. Is it because of the direct injection?
With GDI the low pressure side is module/pwm controlled, right? If so: are there data pids for desired and actual pressure? Did you test the gauge on other vehicles recently as an excessive fluttering of the needle is not something "typical" to GDI systems in my book.
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The only Pisa I have are for the high side that I can see. The desired and actual match. Do t see one for low side though. Yes it’s pwm. Probably just current ramp the pump and go from there.
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