LB7: P0093

[LB7Diesel]

I need some input from you guy's on a P0093/P0102 code a friend is getting. I've done a bunch of research on this and I've come up with 3 causes. One was dry rotted fuel lines, and the other being the cp3. I've ruled out the FPR due to it being replaced. I wanted to see if anyone has had this issue and it turn out to be bad fuel lines.

I did a log of RP and the pump will make 23K for a short moment and then drop to 15K on a commanded 23K. This happens when the truck hit's OD and then it codes. Truck has no power adders at all..

Weak cp3?

Fuel filter has been changed, balance rates are great.


Edit: Also, is there a way to flush out a cp3 before you install it to make sure it's free of debri?

 

[TrentNell]

its kinda sounding like the cp3 to me , i dont know of any other way to test then to comand max pressure on a stock pulse width tune and compare desired and actual . only other thing would be to maybe check return rates as well if they show up fine then you got your answer . dont know on the fuel line ?

 

[McRat]

What model engine?

 

[LB7Diesel]

01 LB7, lot's of miles.

I was trying to get my scan tool to work so I could control the cp3, but the pos wouldn't work for me Trent. I read alot on TDP last night and for the most part they all had bad cp3's with a few bad rubber fuel lines, and FPR thrown in. But I didn't see really any where the cp3 would still build 23K. Most would top out at 20K and then fall to the teens.

What's with the MAF low voltage code..That one kind of confuses me too?

 

[McRat]

For LB7's, CP3 failures are routine. More rare for LLY+'s.

Put a vacuum/pressure gauge on the fuel supply port. If it is reading little or no vacuum, it's the CP3.

 

[LB7Diesel]

For LB7's, CP3 failures are routine. More rare for LLY+'s.

Put a vacuum/pressure gauge on the fuel supply port. If it is reading little or no vacuum, it's the CP3.

Thanks! Will do.

 

[racinmike77]

the cp3 has pistons just like a motor, with high miles it will wear out too

 

[JOHNBOY]

I have seen a sensor go bad also but it sure sounds like the cp3 is weak. A weak releif valve might be the cause also. Not as common on LB7s as LLYs but it happens

 

[JMK777]

what was the problem a 0093 on mine was bad injectors

 

[2500HeavyDuty]

check return rates on the injectors

and check balance rates cold