Vortec rough start

[JalopiedAllOver]

97 K1500 5.7. I've had some rough starts, seems more likely when cold. most of the time it takes a second crank to go and the sound makes me physically cringe. New cap, rotor, spark plugs and wires. Gonna cut a new ignition wire i think since mine is funky. Anyone have similar issues? Gonna replace fuel filter soon.

 

[Schurkey]

The Usual Three:

1. Verify fuel pressure at prime, at idle, and under load. Most fuel pressure gauge assemblies have a push-button pressure release connected to crappy vinyl tubing. Route the tubing so it empties into a drain pan, then push the button while the engine is running. This simulates higher fuel demand if you can't check fuel pressure on the highway. Fuel pressure should remain steady even with fuel flowing down the pressure-relief tubing. How old is the fuel filter? Have you ever dumped a bottle of Chevron Techron Complete Fuel System Cleaner into the gas tank? (Recommended at every oil change.)
   
2. How old are the usual “tune-up” parts and procedures? Make sure the ignition coil will reliably fire a spark-tester calibrated for HEI when the coil is fully warm, and misted with water from a squirt-bottle. Cranking compression test of all cylinders while the spark plugs are removed. Verify EGR, PCV, EVAP, and Heated Air Intake (if used) systems for proper operation. Verify proper initial timing (TBI) and electronic spark advance (TBI and Vortec). Replace old O2 sensors unless you can PROVE that they're working properly—old O2 sensors get lazy, they don't provide accurate data, but they do provide “data” that fools people into thinking they're “working”.
   
3. Connect a scan tool (NOT a crappy “code reader”) and look for “codes”. More important, look at the data stream to verify EVERY sensor and computer output. Verify fuel trims during the time that the vehicle is not running properly. Look for misfire counts for each cylinder (OBD2 only.) “Codes” have official diagnostic procedures that will be found in the service manual set for your vehicle. The service manual set can be downloaded from the links in the Sticky thread section of the Engine forum on this web site.

 

[JalopiedAllOver]

i'll check the spark advance and fuel pressure. Heard some noise about crossfiring distributor cap. I don't know about the O2 sensors, I straight up drove without them plugged in and the start wasn't affected (although the ride was definitely very crap and loud). I know the ignition wire is a bit off since I've had to spin around the wires once or twice to get it starting.