miss feeling..AE help

[travis182008]

truck is a 01 with 110k miles. i have a miss feeling at idle. i notice the truck has a pulsing vibration feeling.. if you look close enough the rpm move up and down very slightly. i have a new icp and recently got all new stock injectors replaced with reman stock injectors.. it didn't fix the problem.. i just got my ae in and it threw some codes. i ran the cylinder contribution test and got p0284 cylinder 8 injector circuit contribution/ balance fault.. could that cause the miss feeling at idle.. it also said code p1280-icp circut low and p0472 exhaust pressure sensor low. what do these mean? thanks guys

[Evil Eye]

Yes, that means that cylinder 8 is not working properly and would definitely cause the "miss" that you are feeling. You might want to check your UnderValveCoverHarness (UVCH) wiring harness for any chaffing especially around cylinder 8. Also, clean your back pressure sensor. The ICP circuit low could be a chafed wire or a weak HPOP. Get the other items checked out and go from there.

[NoRalPh]

You have to be careful though,,, with the introduction of the Grey CPS, it's now not unusual for #8 & #3 to be falsely labeled as failing the CCT.

Black, Grey, & Dark Blue Cam Position Sensor Perdels Test - Diesel Forum - TheDieselStop.com


Could the 1280 be from the previous ICP? Did you just change it? If not, clear codes, monitor the ICP and IPR%. You might also want to do a Buzz Test and listen for #8 to be different than the others.

[travis182008]

hey sorry i will add some back story..i took it to ford and they said bad icp so they replaced it and the wiring and i think the under valve harness on the #8 side( i will check that to make sure) the problem still was happening.. then i took it to a guy and replaced all injectors still happening.. ii got the AE in today.. is there any way i could look at the icp % and the duty cycle and will that tell me anything? i kinda messed around with it earlier and got 470 psi icp and 10.5% duty cycle at idle.. i don't know what that means

[travis182008]

#8 sounded good.. i will go out and clear everything out and they try it and see if i get anything again. i cleaned the back pressure sensor but not the tube. i will clean that tonight