fueling problem-60%,dual CP3

Dallas S

Active member
Jun 17, 2009
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Alberta
06 LBZ. 60% injectors, ATS dual CP3 using stock LBZ pump in valley, and a stock LB7 pump up top.

just finished a mild build on this truck including the 60%'s, dual CP3's, S475 over stock. Just started the truck up today with some fueling issues. After tracing down a fuel leak I went for a quick drive. truck idles fine but there is no power. feels like the pedal is dead. rail pressure wont go over 15k as per the gauge. when it final gets to 65mph the rail gauge will show 14k psi and jump to 15 every now and then, and sometimes it will jump to 17-18. when it does jump its only for a split second but there is a noticable power difference.

I have check all conectors, fuse and ground for the ats controller. everything checks out. I deleted the intake heater and EGR, turned the codes off for both.

any ideas what to check? im kinda lost right now as ive never delt with twin cp3's before. I think its a problem with the cp3's but? the tuning is the same as when I tore the truck down. 3000 pulse width which i know is to much but i cant even drive the truck to try and tune it. theres no smoke either, does smell rich at idle tho.

any ideas?:angel:

should also mention there are no DTC
 
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Dallas S

Active member
Jun 17, 2009
486
33
28
Alberta
other thing, MAF is in a 5.5" tube now. went to B0201 and went up 30% just to see if that would help. nothing changed.
 

ZeroGravity58

Well-known member
Mar 23, 2008
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just thought id ask but your running a LBZ pump in the valley with a LBZ reg are you running a LBZ reg on the second pump also or the LB7 reg? If so both regs need to be the same.
 

Dallas S

Active member
Jun 17, 2009
486
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Alberta
presure maxxes when one pump is unpluged or fuse is pulled. I believe the problem is the reg difference. top pump still runs the LB7 reg. is there a way to tune around this? if not how much is a LBZ reg? the plastic clip on the LB7 reg is broken anyways... would be nice to be able to tune around this for now tho.
 

custom8726

Active member
Feb 25, 2008
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$160 for a new reg. arrrrg oh well. anyway to tune around this while I wait?

Not really, from what I am told they ask/demand different voltages. I would assume it is possible if you are knowledgable with EFI and want to spend the time messing with it, but I would just switch the regulater and save yourself the headache..
 

Mike_S

OOPS!
Nov 18, 2009
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$160 for a new reg. arrrrg oh well. anyway to tune around this while I wait?

No. The voltage requirements are completely inverted from eachother. One is full open with no voltage and one is full open with full voltage. I'm not sure, but don't be surprised if you have a damaged controller from running the wrong regulator on one circuit and the correct one on the other...
 

05smoker

I'm officially done!
Mar 30, 2007
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Lebanon, OH
Don't tell my truck. It has one LBZ and one LB7 and seems fine.:eek:

Unplug it and see if it goes wide open. Any codes? Could be relief valve, could be cracked injector body, ....??
 

Mike_S

OOPS!
Nov 18, 2009
803
0
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40
Idaho
Don't tell my truck. It has one LBZ and one LB7 and seems fine.:eek:

Unplug it and see if it goes wide open. Any codes? Could be relief valve, could be cracked injector body, ....??

Odd...wonder if the location of which pump each is on makes a difference...
 

Dallas S

Active member
Jun 17, 2009
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Alberta
so what is it? lol

injectors should all be fine. I just swapped tips. all disks are there.

truck idles and starts great. just no power. feels like a clogged fuel filter but I just replaced it. no codes. fass 150 feeding the pumps.
 

ZeroGravity58

Well-known member
Mar 23, 2008
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I just threw it out there. I know they do require different voltages at idle and part throttle. When I changed from my lb7 to my lbz reg I had to rescale the b1010 table. At wot it won't make a difference as they both call for 0 volts to make them both go wide open. I was thinking maybe it could be messing with the controller also. I ran two lbz regs when I had my dual fuelers. You could lower the pulse width to start and see what happens running 60 overs and a 3000us pulsewidth you are demanding a lot of fuel.
 

Dallas S

Active member
Jun 17, 2009
486
33
28
Alberta
ive only unpluged the LB7(top pump). when I restart the truck the rail presure gauge spikes to 30k and I shut it off. same when I pull the fuse out for the ATS controller. havent unplugged the stock LBZ pump. I will load a stock tune in tommorow and see what happens.

I dont think its because of the pulse width tho. it does not smoke at all, doesnt try and take off, its just sloooow. fuel lines should all be correct. I will look tommorow again. -25*C out here so the less time I spend outa the truck the better.

also, what the consences about the different regulators? should I get a LBZ reg for the LB7 pump or? the throttle only has 1/5 of motion. ive tried WOT and there is no difference as 1/5 throttle. only thing that happens is the tranny down shifts and tach goes over 2k and It fallls on its face.
 

FMOS

Hard Up
Nov 19, 2008
352
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Fort McMurray, Alberta, Canada
Sounds like its in limp mode for fuel related issues. Are the limp mode tables altered from stock? Do you have the limp modes disabled by other means? If you dont, are the codes set to not report and thats why nothing comes up?