97 Silverado wont fire (many parts replaced) - theory where to go next?

[PA Silverado]

97 Silverado, 5.0, 5spd, 137K miles
Symptom: Periodically, the truck will not fire up - it will turn over but not fire. Seems to be most common after it rains or is humid. Sometimes, within a min or two of start up, it wants shutter under load. Re-load the clutch, and it goes fine after that. Within a few seconds after that, runs like a top. Related or not, last winter, occassional hard start, and sometime an engine code, usually right bank.

When it would not start, visually verified spark and fuel pressure of about 58 PSI. Fuel pump has since been replaced.

Replaced recently
- Ignition Control Module
- MAF
- Distrib Cap, wires, plugs, and "spider"
- One or all O2 sensors
- Fuel pump, filter and sending unit (because it was a little under 60 psi and original equipment

I am at a loss where to go next. Computer replacement? If so, does it need programmed? I might just swap out the distributor cap regardless if it is recent or not.

 

[zora]

First of all is that a typo on the year, 97?

 

[PA Silverado]

1997 Silverado.

 

[zora]

C1500, have you considered a bad crank sensor or the harness connected to it?

 

[PA Silverado]

Its a K1500 Silverado, but I will definitely look into the crank sensor.

 

[PA Silverado]

Update for those who might be researching similar:
Last week, after rain, truck would not start. Ran a hair dryer on cool, high at the distributor area for 10 mins. Truck started but was a hard start. Ran it for 10 miles - seemed to have a miss under acceleration. Ordered Delphi distrib cap, rotor and ignition coil.

Two days ago, truck would not start after a rain again. Swapped the ignition coil only. Truck started right up, and has run good for past 2 days. If it acts up again, swapping out distributor cap and rotor.

 

[zora]

Based on your original post it looks like the coil is the only thing that had not been previously replaced. Good luck.