1997 Tahoe 4x4 Misfire P0305....

[Surfingfool21]

I have a 97 Tahoe, 197K ran really good up to last Monday morning. Fired it up to go to work. Had a really bad misfire, SES on and flashing. Came up with a P0305 code. I checked the following:
Plugs- Good (no wear, they are not that old, replaced them anyway Delco-12)
Wires- Good (Swapped the wires to see if the miss would follow, no change)
Compression Check- Good (All cylinders 200-210)
EGR- Good
PCV- Good
Checked for vacuum leaks- None found, no change in the running
After reading all the posts, I'm wondering if I have a bad injector? I guess I'm looking for validation in replacing the injection (spyder) system?
Hopefully someone has experienced this type of failure, what's the fix?

[Surfingfool21]

Thanks for the info. The engine is a 5.7 Vortec. I had the cap off cleaned what little corrision there was along with cleaning up the rotor. Just tonight I removed the crank sensor. Cleaned the oil and grease off of it. Cleaned the wheel in side just to make sure that there were no connection issues. No change. Still getting a P0305 code. I'll check for play in dist. Tomorrow and post my results. Strange thing about this problem, It ran really good on Friday afternoon when I parked it. Didn't drive it for 2 days and then started it up Monday AM and this happened. Thanks for your post.... BTW, That's a sick 57!

[Surfingfool21]

Removed the cap and rotor. No side to side play (bearings), however if you twist the rotor I get a slight rotation as if it was moving up and down on the gear. How much movement / rotation is acceptable for that distributor? I think the gear is O.K., it seems like it has typical movement of a dist.

[Surfingfool21]

I checked the wire going to the knock sensor. The insulation was missing from the wire. Removed the old wire and soldered a new wire on. No change in the running, still have a miss. I'm leaning towards the injectors....however I'm waiting to see what all you guys have to say.

[Surfingfool21]

Checked fuel pressure, 55 psi. and steady when running. 60 psi. when I shut if off. Has stayed at 60psi. for a while now.

[Surfingfool21]

Ordered the injectors today....We'll see if this fixes it.

[Surfingfool21]

For what it's worth....Replaced the injectors. That was it. I recommend running the fuel pump, get the gas out of the lines and then replace the fuel filter. Do this before you hook up the fuel connection at the engine. You want clean gas going thru those new injectors. Hope this has helped someone that has this problem.