Who knows their stuff....?

[Toms01PSD]

Riddle me this...

AE keeps throwing a P0284 #8 contribution/balance fault when I do the cylinder contribution test. I've done it multiple times now. I started the test during each start up and the truck would romp like it has a big cam in it. Finally smoothed out and when the test completed my 'service engine soon' light went out and my idle changed... What the heck am I dealing with here? lol

Additional info:
Knocking, possible #8?

01 7.3 117k miles on the odo.

[jesilvas]

CPS will throw that code sometimes.
The romp is usually because the #6 injector fires right before #8, depleting the oil and fuel rail for the #8, hence the reason for the "long lead" injector. The romp will happen to me when the motor is pretty cold. That's cause the oil is really thick and the HPOP has a hard time replenishing the HPO rail in time for the #8 SOI event.

[Jarrod B]

you have the grey cps aparently. it will do that.

[Toms01PSD]

I've ran the cylinder contribution test more times than I can count and it keeps throwing #8. Could that still be a CPS issue?

The dealership did the CPS under recall or something. PO hadn't done it so I took it in and had it done. Which CPS do I need to get to solve this problem? Will this issue also be intermittent?

I just came back from running the crap out of the truck and it threw a P0269 Cylinder #3 contribution/balance fault. The #3 exhaust port is also cooler than the rest on the passenger, sign of a bad injector I presume?

[Jarrod B]

i had a black cps and it fixed my cct errors.

[jesilvas]

Black, Grey, & Dark Blue Cam Position Sensor Perdels Test - Diesel Forum - TheDieselStop.com
GOOD read about the CPS issues.

[Toms01PSD]

Originally Posted by Jarrod B

i had a black cps and it fixed my cct errors.

Did your truck throw more than one? This is the first time it's thrown the #3.

Also, is the black CPS the 'fix' CPS? I'm reading the thread and it appears I just have the 'recall' CPS in right now?

[Jarrod B]

it was always #8.

[Toms01PSD]

Originally Posted by Jarrod B

it was always #8.

So how does #3 get thrown in the mix? I'll try a new CPS and see what happens I guess.

[Toms01PSD]

Originally Posted by jesilvas

CPS will throw that code sometimes.
The romp is usually because the #6 injector fires right before #8, depleting the oil and fuel rail for the #8, hence the reason for the "long lead" injector. The romp will happen to me when the motor is pretty cold. That's cause the oil is really thick and the HPOP has a hard time replenishing the HPO rail in time for the #8 SOI event.

I forgot to mention, 75+ degrees isn't exactly a cold start. It has also done it when i've started it, let it run for 5 seconds, shut it off, and re-started.