obd code p0171 - 1131 engine wont start

[Intercept]

Gonna try and keep this simple and quick,,,,,
Replaced camshaft position synch.
Upon replacement removed upper plenum and egr back pressure sensor to gain access to replace part. Upon reassembly mechanic broke egr back pressure sensor.
I replaced the back pressure sensor, drove it for a few days then eng. light came on. I checked the codes with SCT tuner and it came up with codes 1000 and 1131. I reset it and it came back on, same codes as the first time. I had the car programmed with a 87 octane performance tune from SCT. I reprogrammed it back to factory program and the car ran for about a couple of days before throwing codes ..... 1000, 0171, and 0174.
Ran the vehicle 15-20 miles today eng. light came on. Came home and parked car and left it to sit for a couple of hours. Got in the car later to clear code and the car would not start. So i cleared the code to see if it would do anything, and it would'nt start.

Did the SCT tuner screw with everything, bad egr, maf problem, vacum line leak................ ???

If anyone knows anything about this scenario please reply!!! Cause i am about to run the s.o.b. off a cliff. Thanks,

[behlinla]

First, please specify your engine in your signature. Do you have the OHV or DOHC engine?

Okay, so you have lean codes. You probably have a vacuum leak somewhere. My guess is that you forgot to connect something when you put the intake manifold back on or else you reused the gaskets and they aren't any good.

If you took the EGR valve off, check to make sure the EGR valve gaskets are installed properly. I think the DPFE is fine now.

I should also ask, do you have an aftermarket intake on and is the MAF clean and connected?