bad injector = low icp?

[lugnut]

Could a bad injector cause low icp?

[twoicebergs]

Only if is the top O-ring that has failed. I doubt the lower one would drop it much at all.

[lugnut]

Thanks for the reply. Do you think if that upper o ring is bad it would cause a miss in that cylinder? The dealer just did head gaskets and four injectors for me. I hooked up Ae and its telling me low icp and cylinder#4 low contribution. The truck loses power past 1/2 throttle.

[twoicebergs]

I am talking about the internal o-ring (not easily replaceable - some kits do not include this one) where the rail slides into the injector, not the external o-rings to seal the injector in the bore.

Since you have AE, what is the ICP reading and what is the IPR doing? How low is the contribution? What happens when you command #4 to off or when you take command of all the injectors? It is possible that #4 is creating the problem, but it is also possible it is coincidental or complementary.

[lugnut]

sitting in the truck with ae right now. unfortunally my laptop battery is dead so i have it plugged in with an extension cord right now so i cannot drive it. but here are my readings at idle. icp desired 637.9 actual icp is 638. ipr is 22.27%. turning off injector #4 causes a miss. when i do the cylinder contribution test all cylinders numbers are all over the place. im not sure if i am doing it right also. here is a list of codes i have.
p0046 turbo/supercharger boost control solenoid circuit range/performance
p0272 cylinder #4 inj. circuit contribution/balance fault
p0603 internal control module kam error
p0674 cylinder 4 glow plug circuit
p1000 obd systems readiness test not complete
p2290 injector control pressure to low
the truck runs pretty good below 1/2 throttle. above that the motor actually quiets down and just loses power.

[lugnut]

also when i try to do koer self test it says test failed unknown error occured.
koeo self tst says test failed the vehicle system is in a incorrect state

[southend]

The top oring that the oil rail slides in is replaceable, and if bad, could cause a miss. But your icp looks ok, at idle.

Sent from my phone that somebody didn't help me get.

[Jarrod B]

yes but not common

[mhatlen]

What is your ICP & IPR% @ 195* in park or neutral ?

1500
2500

[kaya@bernhausen]

the top o ring is part of the HPO system. a leak there means a leak in the entire system. it will not cause a miss at that specific cylinder.

OP, you have a glow plug circuit code for the same cylinder you have a contribution code for. i have a feeling something happened in that cylinder..possibly. if that cylinder showed low on your power balance, i would run a relative compression test at this point.

also, your loss in top end power is probably a stuck vgt or malfunctioning vgt solenoid (your p0046)