New Build - Won't start/run - Errors P0100 & U0121

beznich

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I just build a new Coyote for my S197 (2013 GT) as I threw a rod in my original GEN1. The block is a GEN2, heads GEN2, Intake cams GEN1, Timing components GEN1, GEN1 intake, E85 tune, GEN2 Injectors, LTH, etc.

After installing this engine I am having all sorts of problems getting it started. If it fires up it sounds like it's running on 3 cylinders at best. Extremely rich. After a while raw fuel will start coming out of the X pipe and when I pulled the intake yesterday it had a 1/2 cup of fuel in it when I tipped it over. I don't know how I didn't hydrolock the engine but I got lucky. How the fuel got in there is yet another mystery.

I replaced the MAF, cleaned and dried the intake, blew out the cylinders, and cleaned up the plugs and reassembled. I made sure all vacuum ports were plugged up and tried to start it and again I got the same error and a very rough start.

My tuner has confirmed the tune is correct for my car. I'm kind of stuck as to where to look next. I have a NOID light coming tomorrow so I can check the injectors to make sure they aren't stuck on.

Do I have a ground problem? I only know of the ground on the passenger side of the engine attached to the motor mount and the ground next to the PCM. Is there another I am missing somewhere that could be causing this?

Any help or even a nudge in the right direction would be extremely helpful.

Thanks
 

RED09GT

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I'm not familiar with the 2011+ cars but the 05-09 have a ground from the LHS cylinder head to the firewall as well as the one on the passenger side motor mount.
 

beznich

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This has the passenger side motor mount one but I'm not aware of one on the driver side cylinder head. It's definitely worth a look. Honestly, I'm hoping it's just something this stupid.
 

beznich

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I just looked and there isn’t a ground there. I don’t see any loose wires anywhere either. I have another intake I’m going to throw on there to see what happens.
 

beznich

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I do remember taking that off and I just looked and it’s missing. Now, I just have to find it, lol. If this fixes this problem you are a genius on a whole new level!
 

Juice

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Sounds like a leaking injector(s).
Those codes are normal for a reset pcm p1000 is "not ready for emissions" and U codes can be safely ignored unless there is a module that isnt communicating at all.
Got anyway to look at live data?
 

beznich

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I meant to thank you for your help but I got too excited, lol. Thank you for your help btw!

I was really hoping that was going to be the solution to all my problems but it’s still doing the same thing. The other strange thing is the ABS, stabilitrak, and traction control lights are all on as well. I know the MAF is in the same harness as the ABS so there may be another ground somewhere I’m missing.
 

JEWC_Motorsports

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Did you pinch the harness when putting the engine and transmission back together? That has been known to happen alot.
 

Juice

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I dont have abs or traction control on mine, so I never dealt with integrating a coyote with those systems. Im sure the abs module and pcm communication is putting those lights on.
This will not cause the flooding condition and IS a separate issue.
Keep it simple, work on the pcm and over rich condition. Once that is resolved, than you can see about the abs and traction control.
 

beznich

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I initially thought a sticking injector but it would have to be gushing fuel. These injectors only have 22K on them. I have a NOID light coming that was supposed to be delivered today (which is why I took a day off work) but has been delayed until tomorrow.

Also the Code is P0100 not P1000. The P0100 is MAF Circuit malfunction.
I can log with an X4 on this car but that’s it. It is only running for 5-6 seconds at a time and real rough. I do see O2 readings and MAF readings. I can record anything you would like.
 

beznich

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I built the engine on a stand and then assembled the engine and trans out of the car, then mounted it to the K-Member and installed from the bottom. That went very smoothly and without any issues but it is certainly possible.
 

beznich

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I have another set of injectors that are in my GEN2 NMRA Coyote Stock car that I can swap in.
 

beznich

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I swapped injectors and installed my old BOSS intake and got the same result. I also tested both sets of injectors by applying 12V to them while under fuel pressure and none leak, and they all had a good/even spray pattern. I didn't notice any difference between any of them. This leads me to believe the PCM is either hanging them open or something else is causing them to just dump fuel.
 

beznich

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I found a bunch of wiring diagrams online and I followed and traced all grounds and verified they are good. I'm at a loss of where to continue from here.
 

beznich

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I quadruple checked it, but it sure is looking that way. I’m going to pick up an adapter for my compression tester and check compression first then probably pull the front cover back off and check the timing. I’ll be so pissed if so got that wrong
 

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