LLY: Need Some Fuel System Troubleshooting help

[Lparrill]

I'm kinda loss on what to do now.

Bought the 04 Sierra in my sig, already had built motor, II 20 overs etc. Ran perfect aside from tuning being a little dirty. I drove it back from North Carolina back to Wyoming. Ran great all the way till Colorado border where started white smoking and got a nasty lope. Balance rates on a couple injectors were out of spec so just replaced them with 60% overs, along with a FASS 220 and tuning from Tony @ Ridge Runner.

All injectors are within spec now, doesn't lope like it did before. Occasionally will have a slight lope at a stop sign but not always but it will randomly start pouring out whitish/blue smoke at idle or when stopped but when driving runs clean as hell. No power loss, no blowby, doesn't always lope when it smokes.

Could a bad FPR cause this problem? Any different ideas?

 

[Burn Down]

No codes? I forgot to plug my FPR back in one time and took off down the road, engine sure was rattily... No smoke though that I noticed anyway.

Maybe check your injector wiring harness at 2 & 7 IIRC are the problem ones on the LLY. The ficm harness likes to rub through and ground out where it is tied to the ficm mount.

 

[Lparrill]

No codes? I forgot to plug my FPR back in one time and took off down the road, engine sure was rattily... No smoke though that I noticed anyway.

Maybe check your injector wiring harness at 2 & 7 IIRC are the problem ones on the LLY. The ficm harness likes to rub through and ground out where it is tied to the ficm mount.

Nope no codes. I will check the harness again. It's really strange. Will idle smooth and just white smoke. Other times it will have a little lope and smoke and then it will idle smooth and run clean. Going to start going over wires I suppose. Only does it when stopped in drive or parked.

 

[prodiesel804]

does it have an lly regulator or lbz

 

[Lparrill]

Honestly I never checked. When I get back in town off hitch I will look. I was told it had LBZ regulator when I bought it.

 

[prodiesel804]

if it has a lbz reg on it could be in your tunning.

 

[Lparrill]

Could those possibly be symptoms of a failing regulator?

I will datalog it and send it to Tony when I get the chance.

 

[Burn Down]

What is the fuel pressure doing during the lope?

 

[Lparrill]

What is the fuel pressure doing during the lope?

Rail pressure? I'm not sure. Never caught it loping while I was logging it after I got it started. Will log it again once I get off hitch and back to truck and update.

 

[Lparrill]

Alright. Can't get it to lope again but its still hazing bad at idle or when truck is in drive and not moving.

Attached is a log at idle while its hazing. Any feedback?

 

[Lparrill]

Bump for night crew

 

[Redneckzombie21]

whats your lift pump psi set at? 12 psi is good for duel fuels it can also be the power wire going to the duel fuel box its its not getting good power. i have also seen issues where the rubber fuel hoses like returns being kinked or falling apart on the inside and also the rubber feed lines to the cp3 clasping

 

[Lparrill]

Current lift pump is only at 6 PSI. I need to call FASS and get another regulator spring. Going to double check cp3 wiring today

 

[Lparrill]

Bumpity

 

[Lparrill]

Bump bump

 

[Aaron@LDS]

I didn't read the log, but if your tuning is not for the LBZ regulator you will experience an erratic idle. Not sure about the smoke. Have you called Brent?

 

[Lparrill]

Idle is smooth and I have not got ahold of Brent yet. Was waiting to see what Tony had to say