Fire won't start

[jamie greathouse]

My Silverado ( 5.3 ) fires but won't catch and run . I replaced the MAF , The TPS , the ignition switch . I checked No.1 and No.7 plugs their not fouled . The fuel rail has gas i checked 3 different times and pressure seems consistent . 

[richard wysong]

proper fuel pressure is critical. does it just fire or does it run for a second?

[jamie greathouse]

At 1st it poppped right off , ran 2-3 sec's and died . Now it fires but won't catch . It did want to run with Ether but i didn't want to stay running . 

[jamie greathouse]

I tried cycling the key 3-4 times to build fuel pressure but didn't mame a difference . The fuel shoots 1-2" in the air each time i check the fuel rail for pressure / gas 

[jamie greathouse]

Codes were

P068

P0223

P2119

P0122

i've replaced each part and the ignition switch 

[Sharpz]

your fuel pump is probably shot.  If you spray non chlorinated brake cleaner directly into the tb and continue doing so and it stays running then its obviously a fuel issue.  Check all of your fuses then wires that you can see if all checks out, then  look into replacing the fuel pump.

 

[richard wysong]

see if you can keep it running by spraying carb cleaner into the intake while a helper starts it. if you can its a fuel problem. let us know so we can help with diagnostics

[richard wysong]

do you have the code  definitions?

[jamie greathouse]

The day before 50 deg's ran fine 

the next day 12 deg's let it warm

up , filled the tank Nd noticed a miss and super sluggish and stop lights and signs but would clear out and run fine over 1000 RPM's driving . 

[jamie greathouse]

I searched each code and replaced each part . 

[Supreme Pizza]

Fuel

Spark

Timing

Compression

 

Diagnostics is mainly about eliminating possible causes, until you find the culprit.

 

 

[jamie greathouse]

I agree and am getting my Azzz handed to me with this one . If my fuel rail is full it should run 10-20 sec's and then run out of gas . Thats not what happens . The fuel rail valve shoots fuel 1-2" high consistently so the pressure is in the rail and should be weaker if the pump Is failing or not keeping up . 

[richard wysong]

1-2" is probably not enuff. put a gauge on it, should be over 50 psi. auto part stores have the gauges in their loaner program if you don't have 1

[Supreme Pizza]

To evaluate the fuel system:

 

Check or replace the spark plugs.

Move the vehicle outside.

Disable the fuel pump.

Remove the tube from the air filter box.

Have a garden hose or fire extinguisher handy.

Have a helper crank the engine over using the ignition key.

As its turning over, spray starting fluid into the intake tube from a 90 degree angle.

 

Start with "not enough starting fluid", and increase the volume gradually. (avoid fouling plugs this way)

Attempt to keep the truck running by adjusting the shot of starting fluid.

 

If you can make the truck run, and stay running just by going "puff puff puff" with starting fluid, then your truck has a fuel problem.

 

If that doesn't work, then you do not have a fuel problem.

 

Your are basically replacing the fuel system, to eliminate it as the possible problem.

 

Don't stand directly in front of the intake tube while blasting it with starting fluid. Otherwise, if that puppy backfires out the intake, you will lose your eyelashes.

 

[richard wysong]

codes don't mean replace the part, they are to help with diagnosing the malfunction