Hey everyone, long time lurker first time registering and posting on here. I just put a Ls376 paired with the GMPP ECM in my 99 911. All of my ducks are in a row, Grounds grounded, unstitched power run to fuse center, and switched IGN to ECM. Fuel lines are regulated and receiving a constant 60psi. I have primed and started the motor. It runs for two seconds then dies. I believe I know what the cause is, but need conformation and any insight anyone can offer.
Since this is a custom job I have yet to fabricate my exhaust, in hopes of starting the car and driving it onto a trailer to get it to the fab shop... with no exhaust my o2 sensors are just zip tied to the end of my open headers.
My question, if the sensors are exposed to open air will this shut my ecm and motor off? I'd assume it would freak the computer out because the air/ fuel readings would be way out of wack.
Please let me know your thoughts.

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