Im working on 2002 avalanche and it won't start

Why did you replace cam , crank sensor's an the fuel pressure regulator too ? What is or was missing ? fuel or spark ? did you pull a plug wire an check spark . Does the check engine light ,light when the key is turned to the run position ? Do you have a professional type scan tool ? Do diagnostic's ,not guessing an just replacing part's .
056 Engine Hard to Start or No Start Misfire Scan Data
048 Engine Hard to Start or No Start Scan Data for Starting Problems
(55-62 psi) VIN: (V, T,U)
335-375 (48-54 psi) VIN: Z

What engine does it have ? 2.2 or 3.4 L The 3.4 l has two crankshaft position sensors . A an B one is behind the harmonic balancer an the other is located in the side of the engine block . Hooking up a professional type scan tool could see this.
047 Engine Hard to Start or No Start Scan Data for Ignition

still won't crank ? how's your battery ? starter ? starter solonoid ? if your engine does'nt crank , its dead ! would'nt you check the battery first ? then move on with checking the starter circuit ? seems like your putting the cart before the horse ! first of all, when you run out of gas, you need to replace the FUEL FILTER, your engine just sucked the dirt, garbage, etc., out of the tank. there's plenty of sediment in the tank, don't know how it gets there, but, you'd be surprized ! talking threw experience !!! I operate heavy equipment, its a cardinal sin to run out of fuel !!! you say you replaced the inline filter, which one, up by the engine or the main filter, under vehicle along frame ? are we talking about the same animal, PLEASE CLARIFY !

First i would check the crank sensor by looking for rpm's on the tachometer or scan tool if you see any rpm's then crank sensor is good.Then check for leaking injectors and if they are not leaking then you will need to check the ECM it may have failed.

Check the ignition coil or ignition module something is not getting a spake

two engine systems has things to do with this problem, fuel and ignition.
part of the system you're going to check.
fuel pump regulator(fuel) and if it has spark(ignition).
and/or
have a shop with scan tool to diagnose exactly the other problem(s).

Done cars have a kill switch if they are low on oil. Check your oil. If the oil is good, it may be the ignition switch.

If the engine fires up for a second or two with starting fluid then the fuel pump is weak.I would check the fuel pressure and if its not within the specs then replace the pump and filter.

Hi.

If it does turn over and electrical works, then the problem is unlikely the battery. You can try jump starting. If it cranks when jump-starting it may be a weak battery, starter motor or alternator, but I don't think that this is the problem.

Check if there is spark on all cylinders. Do a code scanning (this car is OBD1, you will need to do the scan at the dealer place or to find a BMW OBD1 tool- Universal OBD2 scanner will not work on a 1994 BMW). If the codes return misfire or mixture related errors check fuel pressure, check sensors and parts that determine the mixture (MAF/MAP, AIT, O2 sensors, IAC and EGR system), check the vacuum system for leaks and check the crank sensor.

Regards.

Ginko

is/was the check engine light on??as far as no fuel try spraying some carberator cleaner in
the throtle body to see if it helps starting.