fuel limp

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
Alright guys,need some help with an issue with the new built motor.Its running and idleing fine but when it hits 1500 rpm it smokes and poppes real bad.In park it will only hit 5x mpa but i can command 160 and get it.no codes that would cause a consurn.glow plug,marker light and such.All mods are in sig and still has stock tune.Big thanks to Mark for helping out with the tuna for this thing ad well.hope the new tunes will fix the issue but i suspect theres more at play here.Thanks in advance.
 

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
So tonight i swaped the ckps,cps,fuel temp sensor,1 top cp3 and all regs all had no effect.with no codes to go by im pretty much just throwing parts at it at this point.Anything im not thinking of yet before i pull the covers and tracing wiring?
 

2004LB7

Well-known member
Dec 15, 2010
6,957
2,136
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Norcal
When you command 160 mpa does it actually make it?

If you unplug the fuel pressure regulator what does it do?

If you unplug the fuel pressure sensor what does it do?

Verify that you have a good filter and you are not getting any air in the lines. Check for chafing on the harness, especially around the alternator and bracket
 

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
Getting ready to put this thing in a corner for a time out,So far I have tested all 3 cp3,s,Gone through the entire engine harness,swapped crank and cam sensors,3 regs,coolant temp and fuel temp sensors.Fuel pressure sensor,Checked valve lash.Changed ficm and new tunes went in today with no luck.I can command 160 mma or unplug the reg and get full pressure but when it hits 12-1500 rmp it spits nd farts and goes no further.No codes besides a u1000 for the srs because of some cut wires..This sucks!Every spare moment for the last month and have gotten nowere.ANY idies?Even crazy ones.
 

2004LB7

Well-known member
Dec 15, 2010
6,957
2,136
113
Norcal
What if you load a tune that runs say 120mpa through all rpms. Then log it. Does the fuel pressure stay at 120 mpa ruling out the cp3, regular an pressure sensor. Or does it drop/bounce around?

This may help determine if you need to concentrate on the fuel system or elsewhere.
 

rgullett83

Active member
Oct 27, 2008
1,607
0
36
Illinois
I still think it may be a reluctor wheel issue. Double check its not loose, and that all teeth are straight and not damaged

Sent from my SM-G900V using Tapatalk
 

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
What if you load a tune that runs say 120mpa through all rpms. Then log it. Does the fuel pressure stay at 120 mpa ruling out the cp3, regular an pressure sensor. Or does it drop/bounce around?

This may help determine if you need to concentrate on the fuel system or elsewhere.
Pressures stay stable but wouldnt climb past 1500 no matter the pressure, Was messin around with the airdog thinking it does seem like a fuel issue and it came to life for the first time since it was built.what a good feeling but might ditch the dog and put the fass on.

I still think it may be a reluctor wheel issue. Double check its not loose, and that all teeth are straight and not damaged

Sent from my SM-G900V using Tapatalk
We pulled the ckps and made sure the teeth were straight but it could be the terminals are not making contact.Thanks for the replys on this gents.swapping plug ends in the am and il report my findings.hope to get it on the rollers at mbrp next wknd if all goes well.
 

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
It runs:woott:swapped out the new cks out of big bertha and fired instantly.New sensor and the used obe were duds.More money well wasted but cant thank you guys enough...again:hug: