lq4 with 4l80e swap into 91 c1500 stalling problem. HELP plz

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Mannyb

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hi everybody I've been doing this swap for the past 2 months and am so over it lol, but I've been lurking this site since the start of the swap has given me tons of helpful info but i can't seem to find anything about this issue so hopefully you guys can help me. i finally got the truck up and running last weekend it started up strong and idled great for about a minute then after that it started stuttering a little bit then when i reved it it started to bog down i let it catch back up to about 1k rpm then id rev it again then the bog would just get worse and worse until it finally just died its done this multiple times. I've ran the codes on it and it gives me codes for the map sensor and accelerator pedal sensor and the tpi, I've tried replacing the pedal sensor and rescanned and still did the same thing, rescanned it and it gave me the same map code. I've done a duel pressure test and when it primes it goes up to 60 then when we start it up is stabilizes at 55-58. i did replace the fuel lines and upgraded the fuel pump on it and it has a corvette filter/regulator on it as well. I got the motor and tranny with a modified harness and tuned edu from some company online they said they tuned it and all that and it ran fine so I'm not to sure if its a possibility that it could be the tuning?? i just don't know. the harness they gave me had just a few wires i needed to hook up to run i got them all connected except for the speedometer wire which I've read if the vss isn't connected it could mess with the idle and stuff. umm and i have long tube headers just dumping right now until i get everything else hooked up so its like dumping the exhaust right on the plugs on the left side of the tranny not sure if would've toasted something or whatever but its probably worth mentioning. like i said any help would be awesome not really wanting to take it to someone to diagnose lol and thanks for taking the time in reading this. first post on this forum so if I posted this in the wrong place or something plz let me know.
 

RDF1

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First thing...
What year LQ4 and what throttle are you running? Cable OR Electric?

What injectors? Factory?

Do you have a way to look at the live data while engine is running?
Bluetooth OBDII adapter is awesome. $12 and $10 for the app on your phone.

Is coolant temp sensor hooked up? Do you have a way to see what temp it is seeing?

You said It was throwing a MAP code. What was the number?

MAP And TPS reading would let you know instantly where your issue is.

Any intake vacuum leaks?

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

RDF1

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Any more information on this?
 

Supercharged111

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If it's throwing multiple codes, they're probably related. Maybe they share a ground or a 5V reference signal. That's where I'd start.
 
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