Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
infact i have the same problem on honda pilot 2016, the same thing happening as scanner danner described, i did almost all the test danner did, except watching the injector tip with camera, i even removed the high fuel pressure pump under the intake and smell the oil around where the pump touches the cam lobe but no sign of internal leakage... blocking pcv hose does not show no sign on scan tool... infact i have p0172 & p0175, the soon as the car enter into closeloop at idle, the fuel trim for short trim speed to negative high figure. changed air flow sensor same, did alot,but still but i noticed something that when i disconnect the pcv hose that connect to the intake, and let little fresh air enter, the negative start to change to positive state, this give me the clue that my O2 sensors are not bad, they re working, cos if they re lazy or not good, like they should not react when i introduce fresh air into the intake.... am thinking of telling the client to get the injectors brand new but i dont know if he should add the high pressure pump, even though if like it leak into the crank case, like blocking the pcv hose or sealing it from connecting to the intake, should show a reading but it does not update or give a sign of change to the negative trim...
First time answering a question on here so be easy on me lol. I work at a honda dealership, have been a Honda/Acura dealer tech for 20 years and these fuel injectors are not very reliable. We have fixed many of misfires replacing high pressure fuel injectors. They chalk it up to debris from the machining process causing the tips to become clogged and or leak. I would recommend replacing the fuel injectors and high pressure fuel pipe.
the new injectors, are they redesigned to correct future error
